We had a similar problem at work in the late 90s. A member of staff reported that their mouse would stop working between certain hours of the day. It had apparently been okay in the morning, stopped working over lunchtime then started again later.
On some days it would work perfectly all day long, but on others it would stop working between those hours.
The biggest clue was it would always work perfectly on overcast days, but on sunny days this strange behaviour would manifest again.
Turns out the problem was related to the mouse being a cheap mouse. The case had very thin plastic.
The mouse was a ball mouse, and it worked by shining an LED into a sensor on each of the X and Y axes. On sunny days the sun would completely overpower the sensor due to the plastic case being very thin and on overcast days it would not. On sunny days the mouse would only work when the sun had moved around the sky to cast a shadow over where the mouse was being used.
Reminds me of a problem that I had (many years ago) with my iPhone 4 - if I tried to boot it in a dark place, it would get stuck on the Apple logo in an infinite boot loop.
Turns out some versions of the Pangu jailbreak for iOS 7.1.x would crash during boot if the reading from the ambient light sensor was below some threshold. To this day I don't know the exact explanation of this bug, but it seems that Pangu included some unnecessary code that messed with the light sensor [1].
If you don't believe me, there is a huge reddit thread[2] with a lot of people confirming this.
That's funny, there exists a similar issue with the LG G7 that a friend of mine ran into several years ago. The fingerprint sensor on his phone just straight-up completely stopped working, and subsequent OS updates did nothing to fix it. At first we assumed it was hardware failure, and he was ready to send it to a repair shop. While investigating it I saw a comment somewhere that it had something to do with the light sensor, and after holding my thumb over it for 10 seconds it "magically" started working again after 4 months of being completely non-functional.
Seems unlikely. I don't have access to the paste but from the comment below it I think it's probably a false positive that Pangu was doing something with the sensor. (Not that I don't doubt that the sensor could be the problem, it's just that the code is not very conclusive.)
I had a similar problem, but in the opposite direction. My cable internet speeds at home were fairly good (for the US, anyway), but sometimes would absolutely bottom out. Not dead, just glacially slow. After troubleshooting everything under the sun, I came to realize that the problems would happen not when it was raining per se, but when it was heavily foggy or misting. Normal to heavy rain was fine.
Called the cable company, tech came out. Everything inside was fine, but the cable from the main line to the house had a tiny cut in one spot, not enough to really affect the connection, but enough for ambient moisture to work its way in and foul the connection.
on dslreports or broadbandreports there's at least two instances of me complaining about two cable companies because, at last, it was figured out there was moisture ingress in the LE (line extender, usually on cable lines on poles). The only common denominator was it happened during prime time, every night, and went away around midnight.
The other common denominator was the cable company refusing to believe it was an issue with their equipment; this meant it took a couple of months of calling them every night until they finally sent a technician and a manager to my house to verify that I wasn't wrong, leaving my house, coming back 15 minutes later to say "it'll be fixed tomorrow, there's a problem with the LE balance up the road" - and then the issue is resolved.
Now this doesn't sound so bad, until you learn that the first time this happened to me, i had only VoIP - so the internet would start to foul, i'd call the cable company, and the tier 1 would reset my modem at some point, and then i wouldn't be able to call back until after midnight (or whatever), when there was no longer a problem. So after a week of this, i would walk 30 minutes - one way - to a pay phone (remember those?) once the internet slowed, call them, explain that i couldn't do anything they wanted me to do physically, since they disconnected my phone line every time i called.
This is what happens with a de facto monopoly.
I will never pay suddenlink another dime, even if they're the only terrestrial provider, for whatever reason.
A customer's DSL connection dysfunctioned every evening during December - but worked fine the rest of the year... Culprit: interference from nearby Christmas decorations leaking EM all over the place.
A customer's DSL connection dysfunction's frequency increased mornings and evenings. Culprit: the lift's electric motor leaking EM all over the place.
A bunch of DSL connections degrade when traffic increase... Crosstalk in big cables of course !
The sort of fun incidents that take a good while to troubleshoot... I'm glad we are migrating away from DSL to fiber: either it works or not !
Having had to debug many of such cable issues in the past, it's baffling to me that cable companies aren't proactively monitoring for things like this.
They have all the data available on their end, as far as I can tell! (Unless DOCSIS modems somehow don't have a standard "signal receive report" functionality?)
Common issue in Ireland for DSL customers. Damaged copper cabling would leak water when it rained causing dropouts and lower speeds. Telecom engineers would call out on days when the copper had dried out and be unable to find any fault. Turns out correlating such reports with weather reports is hard. :/
I ran into a similar issue, except internet and phone would get really bad on a cold morning.
Tech showed up around noon, saw I was indeed having a bad connection, went and checked the signal at the junction box for the street (can't remember what you call these) and everything was normal there, so he closed it back up again and double checks the signal at the house again, but it was fine. He walks the lines to double check but everything looked normal.
His best guess was that moisture was condensing ever so slightly inside the junction box that morning, and was let out as soon as he opened it at around noon, which fixed the problem.
Moisture in copper cables is what slowed me down too. It was in a section up the road from me.
However now that fibre is installed, it’s glorious and works in the rain.
I had a similar problem, due to an old line running to my house; liquid getting in, etc. And when it acted up, I'd call the cable company and be like "look, I can show you I'm losing packets right now... I need you to run tests on your end to confirm". And every time, they'd tell me they could schedule a tech to come out and take a look at it. Only, I couldn't "schedule" the problem to occur when the tech came out.. so they'd come out, declare all was fine, and leave. It was infuriating.
Eventually I called so many times and had so many appointments, that the tech lead gave me his direct number and told me to call him directly the next time it happened. When it did, I did, and he ran some tests, and confirmed there was a problem. I don't know that we ever got it sorted out (it was a while ago), but just getting them to agree there was an issue took a very long process.
I have a garage door that will not close on sunny days.
Same sort of problem. The obstruction sensor at the bottom of the door is confused by the strong sunlight and the door stops closing part way and re-opens.
I've tried a toilet-paper tube around the sensor but that isn't always successful. I really wish there was a laser sensor to replace it with.
I had a VCR back in the day that refused to function if you opened its case. It turned out that instead of using physical switches inside it used pairs of lights and detectors that would give false positive results when ambient light shined on them.
Your mouse story makes me think of the day the CI system at work turned out not to be robust to vibrations.
One day we started having flaky tests, seemingly out of nowhere. We quickly identified that the issue affected tests involving graphical X client applications, but then we struggled to make further progress. The issue was just impossible to reproduce in other conditions... Well, as it happens, the CI jobs were running on some desktop machines we had installed somewhere within our premises. It turned out that some gentleman had plugged a mouse into one of the machines, and left it lying around on the shelf. Since then, when one of the machines was under a heavy load, the fans would spin faster, causing more vibrations, in turn causing the mouse to move, ever so slightly. And for ungodly reasons, this had side effects on tests.
Fun fact: the machines were not on my site, I managed to diagnose this over SSH. I was quite proud :-)
When it’s sunny, my wife’s car can’t open the garage door, and my car requires getting extremely close. Once the sun goes down, we can both open the door from the street.
It turns out our solar panels (or the optimizers, or the inverter) emit radio frequencies that interfere with our garage door opener. When the sun is out and they are producing energy, the interference is stronger than the homelink garage door opener.
A few years ago the garage door openers started working fine. It took a few days to realize it was because the inverter had failed.
I’m fairly certain there are some FCC regulations that would require our installer to fix it, but that relationship soured during installation and I’d rather deal with an unusable garage remote than dealing with them for warranty work.
How old is the garage door opener? Older ones used frequencies that are more susceptible to interference from certain sources. It's possible to buy new receivers to connect to your existing door opener.
The first was a VDSL connection I had at home. It worked great (fast, for the time) except when it didn't. It always failed in the evening. Techs would come out, bless it as being good, and leave -- because of course it worked while they were there. Unless they showed up and it was broken and then they'd declare that it was an outside problem, and that they'd have to get someone else to fix it (because the residential techs can't do overhead work).
I made lots of (very polite) phone calls, which results in more refunds and more service calls. More than once, my driveway and the street in front of my house looked like an AT&T convention.
This went on for months.
I had direct numbers and emails for tier 3 support and the local manager who oversaw this plant. We were all getting to know eachother too well, and there were boots on the ground addressing this problem as many as three times in week.
I eventually noticed that as the days got shorter so did the evening outages...and that if it was a cloudy day, then that day was often outage-free.
I had an epiphany: The problem might correlate with the angle of the sun, and the duration of exposure!
I checked my logs and the past weather, and sure enough: It lined up.
So I reported my findings, even though they seemed like nonsense as the words came out of my mouth, and they sent out some crazy-haired guy with bluejeans and an untucked shirt who was clearly not used to wearing a uniform, and who was also obviously not normally customer-facing.
"I know exactly why they can't find the problem," he said after I reiterated what I'd learned. "Your neighborhood still has old lead-sheathed overhead lines, and nobody knows how to work on that anymore."
"But I'm certified on that. I'm going to go back to the shop, pick up a bucket truck and get your line fixed. It will take me most of a day to do this, but I will be back when I'm done."
And it was getting pretty late, but he did come back to let me know that he found some things and fixed them. And I don't know what those things were, but it was fine after that -- and it stayed fine.
Thermal expansion letting cosmic rays leak into copper pairs wrapped in paper, tar, and lead? Who knows. I certainly don't know.
I've never encountered that stuff professionally (and it isn't your grandfather's 25-pair cable) and as this dude said, "nobody knows how to work on that anymore."
On some days, exclusively in the morning hours, the printer would fail to detect the start of a new label, printing over several labels.
After connecting remotely and checking the usual (queue, network connection, drivers etc), I asked my colleague to call me, as soon as it happened again.
When I went there, I saw that a ray of sunlight hit the printer.
The windows had shutters, but there was a gap.
Label printers detect the gap between labels using a laser.
And for some reason, the printer's case had a clear window at the top.
I printed an empty label and stuck it on the little window.
I'm amazed an IT department would troubleshoot deeply enough to figure out it was the thin plastic letting in interfering light on sunny days.
I would have guessed they'd shrug at the first sign of trouble, swap it out with a known-working mouse and mark the ticket resolved... unless all the replacement mice were thin plastic too, I suppose.
I'm assuming it was a trackball mouse from the description. The OP said it was cheap so I don't think cost was an issue but from my experience some employees are very particular about their peripherals (don't blame them one bit!). If they're important enough (or maybe just nice enough) I could absolutely imagine spending the time to make sure their preferred device is working properly.
Your car repeatedly doesn't start so instead of taking it to the shop, you... write a letter to the CEO of Pontiac who not only actually reads the letter but also personally dispatches an engineer to waste a week going out for ice cream? And Pontiacs have a known vapor lock design flaw that only you, the letter writer, are experiencing? And you've only experienced it on your ice cream runs? And you've never got the vanilla ice cream but took a little extra long so the vapor lock dissipated and disproved your cute theory about vanilla ice cream?
Seriously, this is one of those dumbass stories that come from your boomer relatives with the subject line "fwd: fwd: fwd: fwd: fwd: fwd: fwd: fwd: re: fwd: fwd: fwd: fwd: fwd: fwd: vanilla ice cream"
Nobody actually believes this story is true, right?
While I appreciate your point, I think anyone who has spent sufficient time troubleshooting complex systems has dealt with similar types of problems, and can grasp the _spirit_ of the story.
In fact, I'd argue the quaint style of the story does geeks a favor: if it's appealing to normies, maybe they'll appreciate us technical folks' perspective a little more.
And having a stranger along for the shopping trip doesn't affect the timing more than the extra walk to the back of the store?
And the engineer is sitting in the car on the first night and it "wouldn't start," which signals the end of the episode for the day. Were they stranded? Did the car start after a few tries, which would have given a huge hint about the root cause? Surely the engineer who had reproduced the issue would quickly narrow it down by running diagnoses on the car itself.
But the family dynamics are the most improbable part here. How does the family have this predictable routine and not simply stock up on ice cream? The family has enough kids that the consume a whole $unit of ice cream per day. So with that much chaos in the house, how does the dad justify going out for a drive after dinner when the chaos of family multi-tasking (cleanup, chores, homework, bedtime) is at its peak? "Oh, look. Out of ice cream again. I'll be back in a few!"
Another similar anecdote I heard before was related to a wireless device, and some employees flying a drone during their break, generating interference.
My parents have some old Gateway amplified computer speakers. Came with the 386!
They still work perfectly... except for a regular pop of noise every few seconds that would intermittently show up, that scaled with the volume setting.
It turned out, their portable phone (read: landline with short-distance wireless RF handset) would ping from the base station to the handset, if it were off the cradle, which was being picked up by the unshielded line-level audio cable and amplified.
Moved the base station further from the cable, pop disappeared.
We did a lot of wireless (2.4GHz range) sensor development at my last job. It was a rule of thumb to avoid any testing at lunch time since the microwave generated so much interference, everything would fail when someone wanted to heat up their meal.
reminds me of testing out a pinewood derby track in my backyard for our cub scouts pack. It had an IR sensor that would detect the cars at the finish line. When someone was standing next to the finish line, it worked flawlessly. Otherwise, it was very flaky and randomly would trigger without the cars trigger it. I pretty quickly surmised it was interference from the direct sunlight, so we put up a pop-up shade over it and it worked flawlessly (without someone standing nearby, coincidentally casting a shadow). The other dads were amazed that I figured it out, but it's just one of those things you learn from experience (and some background knowledge).
This happened to me in my first job and it took me weeks to figure it out. The penny dropped and I put tape around the thin gap in the casing where the top joined to the bottom and it fixed it immediately.
This is a secondhand anecdote, but it’s pretty funny. Back in the days of server rooms, a friend’s server for his company would reboot every day around 5pm. They checked everything they possibly could with the OS, they would be logged in and running checks on it and it would spontaneously go offline for about 5 minutes and reboot every day. Finally they decided to go stand in the presence of the server around the time it goes down every day. They watched a cleaner come into the room, unplug the server rack, plug in their vacuum and vacuum around the servers, and then plug the server rack back in.
Oh I have a similar one. This one is first hand, I was in the room when we were debuging the issue.
We were developing a smart camera product which were counting traffic on a road. So for example a city council would install this camera somewhere on a road and it would generate statistics of how many lorries, and passenger vehicles, and motorbikes used that road.
One of our cameras exhibited a problem where it restarted every day around roughly the same time. It wasn't exactly the same second though, in fact there was a clear pattern to it. One day it would restart at 19:12:10 and the next day two second later, then again the third day two more seconds later. (not the real timestamp and i don't remember the real time deltas either, but there was a clear progression)
After much debuging we learned that the issue was that as the sun was settling some street furniture projected a shadow in front of our camera. Our software wrongly concluded that it is a vehicle and started collecting information about it for classification. But of course shadows creep a lot slower than real vehicles so it run out of memory before the "shaddow vehicle" has passed out of the frame. And once we run out of memory the system froze and then got restarted by a watchdog.
Turns out the pattern we have seen in the timestamps was caused by the angle of the sun changing which made the shadow trick our algorithm just a little bit later every day.
I mean it actually happens. Not powering down the actual machine, but in my last house the landlord had a cleaner visit every fortnight. Occasionally I came home to find downloads broken or my remote connection would drop randomly in the afternoon. We lived in an old house and had a wifi extender to reach the upper floors (and not enough sockets). The cleaner would unplug the extender to vacuum the kitchen and half the house would go offline.
The ice cream story reads too much like a dramatisation to be truly believable, but accidental and repeated unplugging is common I expect.
I think the vacuum story gets retold because it's so close to real-life stories.
The UPS on a server I manage would trip once a week around the same time. The old story came to mind and sure enough, once a week it was time to vacuum and someone would plug in a vacuum cleaner into the same circuit (700W vacuum cleaner on a 100V/15A circuit), causing enough voltage dip to kick the UPS into gear.
Essentially all these stories are apocryphal. Even this vapor lock story.
Sorry but even before today, having a automotive engineer sent to a random person's home over what clearly sounds like a quack letter seems implausible to me. The dictates of capitalism, human resources, and the politics of the workplace would make this difficult if not impossible. Even in the past when there was more human capital in support positions and more of a sense of customer service.
Way, way too many suspicious stories involve high-level people being involved in trivial issues. I just find it all pretty suspicious. Real stories tend to start with poor customer service at the dealership and being mocked by managers and mechanics. Not some unrealistic ideal white knight manager sending off engineers to people's homes. Imagine how many weird letters a place like pontiac gets. They don't have the manpower to do this if they actually chose to do it, and engineers might balk at the idea of doing at-home support too.
Pretty much any "idealized Americana" business story should set off BS alarms in us. "Oh a trivial problem with your car? No problem ma'am, I'm sending our top engineers over tomorrow," doesn't happen because its costly and unsustainable. Instead ask anyone who has odd car problems. Its endless painful calls and visits to dealerships and mechanics. There's a reason we have lemon laws for cars. Its because whats described in this story doesn't actually happen and people demand restitution.
I don't doubt that someone had a famous vapor lock shopping story (ive heard different versions of this story, usually about a housewife picking up her child from a nearby elementary school), but over the years these stories get modified into memetic structures based on dishonesty because most people are social capital seeking and having a humorous story provides them the immature ego boost they need. So "wow my car had vapor lock when I make quick trips" became "So the CEO of Ford came to my house to look at my ice cream car..." The latter is just more interesting in the market of storytelling.
That is to say, the ONLY reason this story is here is because its been modified to be memeticly attractive. A "boring" (i find old technology faults interesting, personally), but a "boring" story about vapor lock wouldn't make it to places like HN or reddit, which are memetic responders (upvote/downvote mechanisms) and lowest-common denominator (by this demographic) popularity machines. But dress up that boring story and now everyone is repeating it, often times claiming its their story and they know the people in it! The same way the comment you're responding to probably doesn't actually know the famous "unplug the server at 5pm" person.
I personally had a similar situation. We had an accounting firm whose servers we were maintaining, and occasionally the print server would reboot, always between 9 and 10 am. So I sat in there for a week between those hours and noticed the light would dim and occasionally the reboot would happen.
It turned out that the lawyer next door would come in, turn on his PC, printer and coffee pot simultaneously because they were all on the same power strip, and the drain was causing an undervoltage on the circuit the server was on during startup. We had it on a UPS, but it turns out that at the time consumer grade UPS systems only handled outages.
I measured drops as low as to 85 volts, in practice anything under 95 or sou would reboot.
1999, the town hall of a small municipality s/e of Stuttgart Germany. For the 3rd time in half a year me (IT apprentice) and senior developer are onsite to fix one MS SQL db's broken indizes. It's the early afternoon of friday and humid hot, a thunderstorm is on it's way. We toil on and are almost done when at about 16:00 the chief officer turns up and informs us that we have to hurry because at 17:00 all electricity will be cut in the building!
Senior developer and me share a shocked glance.
"Is this every friday?"
"Why yes! We conserve lots of energy that way."
Senior and me share another glance and on impulse I speak up.
"Isn't the weekly db cleanup scheduled for 16:30 PM on fridays?"
The senior developer nods. We spend the remaining hour to fix the problem and then cancel this weeks schedule and manually shut down the DB server for the time being.
Every friday these guys cut the power to the building, causing all kinds of production issues with not only their Netware Server but also the DB server for their collections software (our product). As per maintenance contract we were required to repair the DB everytime which was a hassle and a waste of ressources on our behalf.
In the end it took another month or so until they relented and rescheduled the hard power down until saturday morning so that all servers could shut down properly even AFTER the backup jobs could complete (backup was also totally broken but they never did check or even perform a restore so they never actually noticed).
I think it's more like a common experience. My wife and I both work, so we have cleaners come in every two weeks for a deep clean. We've used several different companies, and apparently it's standard practice to unplug things when a power outlet is needed. They don't unplug computers that have monitors, and they don't unplug things with visible clocks that would need to be reset, so they do take some care not to inconvenience us, but they'll unplug anything else, including NAS appliances, DVRs in the middle of recording shows, etc. When we hire a new company, we make sure they mark down a special request that they not unplug anything, pointing out that we have ample outlets and can help them find one or free one up if necessary. I also replace any network connectors that lose their little plastic locking tabs, because they're likely to slip loose when things get jostled around during cleaning.
funny thing, something like this happened to me. we were on site doing some implementation and went back to the hotel at about 3am.
less than an hour later, we get an email from nagios (i think it was nagios? it was a GOOD while back) complaining the server was offline. we got into a cab and went back straight up (this server was not supposed to be offline ever).
guess what? a maintenance guy turned the server off by mistake while cleaning up the server room -- even worse, he was not even supposed to be there!
this triggered a bunch of security checks and the company found out that most employees had access to any room in the building.
Similarly, we were just finishing up a project for a client and we’re just going through and connecting everything up.
The hardware consisted of 6 color terminals (Wyse 350s I think), the server, and 10 PCs with large, 20” tube monitors. We had these all in my bosses office powered through assorted outlets and power strips. The room was wall to wall machinery.
It was after hours when the janitor came in and plugged in his vacuum. I looked at him, he looked at me, I looked at my boss, who looked back. We then both turned back to the janitor, who looked at us.
Not a word was said as he fired it up. 2 seconds later, the power was out, we blew the breaker. Took us a half hour to get it back on. But it was funny at the time.
Pretty much, server rooms still exist in offices but they'll mostly be for the network infrastructure, with most workloads including email and storage having moved to the cloud. Office365 is a really tempting offering, compared to operating your own servers + staff.
I had a similar experience: I have a permanent dynamic lighting system installed in a food hall / night club. One day about a year after installing the owner called to tell me a fixture was on the blink. The following day, another, the following day, more, but different ones. This was worrying as all the hardware is custom and would be very hard to source replacements for. We investigated lightning strike or other power surge related to construction on the block, water damage, etc. Long story short we found out that the new cleaner, who was VERY VERY thorough, was pulling out the server rack to mop behind it nightly and straining the cat cable terminations.
In the US the "winky" receptacles that go (-|) or (⊣|) - except the T faces the other way - are 20 amp outlets, 120 volts. every receptacle that differs from the "shocked face" means something. Our standard shocked face receptacles are 15A. In hospitals, you need a guarantee that your monitors or assistive devices aren't going to trip a breaker somewhere if someone plugs in a vacuum; making it impossible to use the receptacle for something else is something that only matters after it's too late, i'd think.
This reminds me of a GM minivan that my youngest brother-in-law drove, back in the '80's. He'd gotten it from his father, who was a career GM automotive engineer - and complained that, occasionally & randomly, it would not start. It seemed like the minivan's whole electrical system was dead...
Brother-in-law was known to be "not so good" with cars - so his automotive engineer father didn't take the complaints seriously.
Complaints and emotions escalated, until brother-in-law convinced his dad to swap vehicles for a month, so (he hoped) his dad could experience the problem for himself.
After the problem manifested in the parking lot of the GM Technical Center, and the whole crowd of GM engineers surrounding the vehicle couldn't figure out why the heck the electrical system seemed to be dead, my brother-in-law felt pretty vindicated.
I have a 2009 Mercedes SLK that had the same symptom. It was absolutely fine 99.9% of the time, but one time in a thousand it wouldn't even try to start. No clicks, no indication that it even knew I was in there turning the key. Just dead. And then seven or eight hours later... it would start fine, as if nothing ever happened. Couldn't correlate it to anything.
Had it towed to a service center a few times when this happened. Every time, by the time they got around to trying it (a few hours later)... it would start fine, with nothing to diagnose.
Then, it was 99% of the time it was fine. I was with a group of folks car-camping off road to fly a human powered airplane for a couple days, and... no start. Finally started -- with no sign of any problems -- around noon the next day, and I high-tailed it out of there a day before the rest of the group, because getting stuck there /after/ the rest of the group would have started pushing my comfort level. So at this point it's actually interfering with my life.
I've tried all the usual stochastic troubleshooting (swapping out fuses, light to moderate percussive maintenance, alternate keys) and nothing. Finally it fails to start in my driveway, and I get it towed to an independent mechanic. It's short tow, and it fails to start when it gets there! So now he's seen the problem, and is as puzzled as I am. Of course, when he tries again the next morning, it starts fine.
He proposes two possible fixes: replacing some ECU module, or replacing the fuse box itself (under the theory that it's the connector or connection into the bottom of the fuse box that is having some moisture ingress or intermittent connection). Of course whatever we choose, I won't know if it was right or not until the next time I'm stuck. The ECU is multiple thousands of dollars, and the fuse box is < $200 with labor, so I make the easy choice.
This was six or seven years ago, and that car is still my main and only car. Hasn't had a single mechanical issue since swapping out that fuse box. A good independent mechanic and a good guess!
Finally figured it out after months when I moved a wire and it started, then move the wire close to another wire and it would no longer start. These were wires that would typically be close, so my guess is one of the wires was now generating enough noise that it was bleeding over into some other system and causing it to fail. As the car bounced around the proximity of the wires changed and lead to the random behavior.
I know an older guy at church, whose kids all graduated college - except for one.
His "failed" son is the top mechanic at a Mercedes dealership. He does some supervision, training, etc. But the reason the dealership is paying him $200K/year is his skill at figuring out and fixing problems like that, for the dealership's most desirable and profitable customers.
(That I've heard, none of the mechanic's "successful" siblings are making that kind of money.)
That definitely sounds like a loose connection, not an ECU problem. Usually it's a bad clamp on the battery terminal. Often it's the ground clamp in particular.
The easiest diagnosis is to rotate the cables on the terminal several times to rub off oxide build up, then leave them in an orientation so that the natural tension of the cable forces the clamp into good contact.
A "dead" (low voltage) battery will still cause some indicators/lights to come on when you crank, while a bad connection usually acts like zero volts.
Today's car mechanics are a different breed. The ability to diagnose and triangulate problems without advanced tools made car mechanics quite intuitive and resourceful in the past. I take my car to one such mechanic. I always leave with a bill lower than any other estimate I get and he always finds and fixes the problem.
Wow, it's crazy to see this comment because I drive the same type of car and recently experienced a similar problem.
The car was dead for long enough that I could get it towed to the mechanic and they educed it was a problem with the EIS (electronic ignition system).
The EIS computer was sent off to mercedes for diagnosis, they reported that the computer itself was fine but it was an issue with power. The mechanics traced it back to a bad connection of a wire somewhere.
I have seen similar behavior on vehicles that have a dying alternator. The issue is that one vane of the rotor (or maybe stator?) has shorted and no longer functions. If when the car is shut off and the rotor stops in a particular position the alternator won’t work. Give it some time and with heating/cooling moving things around just a bit plus the act of repeatedly trying to turn it on potentially making it move just a bit, and it works fine.
Seen things like this before. Often a bad connection somewhere, possibly involving material that expands/contracts significantly in response to a change in temperature (turning the module into an inadvertent temperature controlled switch).
Heisenbugs are manifestations of whole-system design failings, where projects are not engineered to facilitate troubleshooting, subsystems are strongly coupled, and everything is just barely held together with baling wire and bubblegum.
That GM vehicles from this infamous era would suffer from maddening, mysterious electrical glitches makes perfect sense.
GM cars are notorious for (sometimes) developing strange problems that would have you think they are possessed with the devil. (Despite post-1990 GM cars being near peers to Japanese cars for reliability overall)
I learned a lot of things from my father. Unfortunately a lot of them were what not to do. Don’t buy cheap tools that you’ll have to replace three times in the lifespan of one that costs 50% more. And don’t buy GM.
Mechanically they may be reliable, but 90’s GM forgot how to make paint stick to metal and had to pay to repaint a massive number of vehicles that simply pealed if parked outside for too long. How?
And there is absolutely no forgiveness in my soul for the Chevy Citation. I joked when I moved to Seattle that the main problem is since there is no salt, there are still Citations on the road and that is unnatural. Their place in the natural order is the junk yard.
i learned that these things typically are grounding issues. it usually came down to a single source of ground being a loose connection which is why it was intermittent. as a personal anecdote to this, as a first car as a teenager, i drove a GM/Chevy S-10 that one day started to have issues where all of the gauges on the dash would just go crazy and the lights would go on and off, and then suddenly just start working again. after taking it to the shop my dad recommended, a mechanic walked out to greet me. after i told him the symptoms, he stepped back to look at the truck model, asked me to confirm the year model. he promptly opened the driver side door, reached under the dash, located a specific screw, hand tightened it as a test, and everything worked. he came back with a screw driver to properly tighten in before sending me on my way free of charge. he told me that specific model was notorious for the screw holding the ground wire to come loose. it would cost him more in time to write up a sales slip to charge me.
> Despite post-1990 GM cars being near peers to Japanese cars for reliability overall
American carmakers really needed that kick in the ass from Japan. Around 1990 was when my parents went from being protectionist, "buy American" to never buying another domestic car again in their lives. They were angry, angry at the reliability difference and angry knowing that domestic carmakers could have done better but instead relied on people like them to buy the flag.
I had a 1989 Chrysler LeBaron that developed insane electrical issues. Windshield wipers would randomly turn on, the radio would change stations by itself. It really did seem possessed.
I mean...it's possible they've improved a lot compared to where they were 30+ years ago, but to call GM's cars "near peers to Japanese cars for reliability" just doesn't hold up.
On Consumer Reports' list of car brands by reliability[0], none of GM's brands even crack the top 10. GMC and Chevy are 20 and 21, respectively, out of 25 brands. (The top 5 include, unsurprisingly, Toyota, Lexus, and Honda—your classic reliable Japanese brands.)
Plenty of cars that intermittently won't turn on in this thread, but I once had a car that intermittently wouldn't turn off... or at least the headlights wouldn't. I assume a relay somewhere was overheating and that was making it stay closed, but I never debugged it, and nor could my cousin who was an auto mechanic. We never tried too hard, though: I would just take the fuse out if it happened and put it back the next morning.
True story: I had that happen to an airplane. I was a student on a long solo flight and on the last two legs of that flight, the engine wouldn't shut off using the usual method of pulling the throttle back to idle and turning off the magneto.
It's been long enough that I don't remember what I did to get it shut off (maybe I toggled a circuit breaker?), but when I got back to base, I made a note in the airplane log about the problem and also left a note for my instructor, who was out that day.
When I came in for my next lesson, instructor mentioned that the next person to use the airplane, also a student on a solo cross-country, got stranded 100 miles away because when the engine wouldn't shut off, he panicked and pulled the throttle hard enough to rip the cable through the firewall. Airplane had to be put on a flatbed to get it back home.
The radiator fan in my Jeep did that in Sudan when it was 48C. Better to have it stuck on that stuck off in those temps!
I just tapped the relay with a wrench and it un-stuck and turned off.
Funny enough that was almost 5 years ago, and it hasn't done it once since in more than 80,000 miles of driving. Not in -35C, not in +45C. Odd little relay.
I'm going to armchair and guess that your brother needed a new battery.
My (GM) car gets really funky startup behavior when the battery gets old. It will often turn the starter fine, but the electronics can get stuck in weird states until I disconnect the battery (essentially a hard reset).
The dealers wanted a ton of money to diagnose the issue, even though I suspected it must have been the infotainment system draining the battery. I just ended up replacing the infotainment system with a cheap CarPlay compatible one and the problem went away.
Problem is I cannot get money from the class action settlement since the original infotainment system is already out and I fixed it myself.
This reminds me of a strange recurring experience I used to have with electronics in my house.
In that house,on certain days of the week at midnight, something that sounded like recordings of political speeches from WW2 would be audibly (but faintly so) from all of stationary electronics. It was so faint, that it was usually hard to pinpoint any one source, and the words used weren't understandable, so it usually sounded like it was coming from everywhere all at once, and like it was an old recording.
This would happen even if they were unplugged. Even if my power went out.
I though I was either going crazy, or my house was literally haunted by hitlers ghost.
Well one day I was in my car and recognized something on the radio that reminded me of this spooky problem I had.
It was the signon of a Catholic am radio station that opened up with Gregorian chanting, and a sermon. This signon happened at the same time on the same days of every week.
Turns out, the wiring in that house was somehow functioning as an am radio receiver, and some common components would vibrate out the audio encoded in the radio signal.
Near my work, there is a roughly 25 foot stretch of road in front of a factory where seemingly every FM station is overpowered by Muzak. I don’t know what the heck is going on in this factory but I have seriously considered contacting the FCC.
> I speak with the Comcast attorney about my call to State's Attorney's office. She says she was unaware that State's Attorney has denied the request to drop the charges, and that she will write another letter to ensure that the situation is taken care of. She also asks about whether the video trap has been installed and is working correctly. I tell her that everything is blocked except for 2 religious channels, 1 Spanish language channel, and the video portion of E! TV. She says something along the lines of, "I guess the signal of the Lord manages to find its way through somehow."
My son's laptop screen kept shutting off while he was playing American Truck Simulator. His truck would drive off the road while the screen was black.
Every time I played on his laptop, this did not happen. He swore he was cursed.
This went on for many days, with many instances where it would happen for him but not for me. Then one day I just sat and observed him while he played, looking for any difference. That's when I noticed his watch band is metal with a magnetic clasp. The position of his wrist on the laptop was tripping the hall sensor, making the laptop think the lid was closed.
Him and I (and his mother) were glad to find out he is not cursed. :-D
While screens of earlier MacBooks could be turned off with a single magnet, my 2020 Intel MBP requires both the left and the right sensor (around the tab and the enter key) to trigger at the same time to consider it closed. It would be nearly impossible to trigger that accidentally. For starters, you'd need to wear two watches..
If it was Tesla they would have forgone any sensor done computer vision on the webcam feed to determine if the lid is open or closed. I'm looking at you, terrible automatic wipers.
This used to hit us sporadically at my university's help desk. It'd also happen if you have one MacBook open on top of a closed one. The magnet could easily line up and it'd shut the screen off.
These are the kinds of stories that made Car Talk so much fun. It was so much more than just hearing about mechanics repairing cars. It was the fact that the situations were so odd and unusual that the stories were interesting. It was also fun hearing how these mechanics had been around so long and seen so many of these unusual situations that they became normal to them. It didn't hurt that they were good story tellers
these days it's "just buy a new carburetor" - i remember rebuilding a few like 20 years ago - on small engines, but now a rebuild kit is, say, $12 and a new carburetor is $20. For an extra $8 you only have to remove two bolts and fasten the new one in, rather than take a carburetor apart and replace gaskets and floats (or whatever, it's been 20 years).
word to the wise - never use the shutoff switch on anything with a carburetor - use the fuel shutoff valve. This prevents gasoline from varnishing your carburetor bowl.
I probably won't use that word again for a year, now, heavens.
Stated another way, distinguish observations (facts) of a story from the inferences--don't dismiss the observation/facts when rejecting inferences. This is analogous to an XY problem.
Indeed. A timing problem was my first thought when I read the title which was obviously provocative, maybe that's because I deal with timing problems often so I got lucky there, but I rejected the idea, thinking the user would have noticed it too. Nope.
I used to do some help desk as part of my dev job, and from my experience, users easily assign any random fact as the source of the problem. Often things like "correlation is causation" or *post hoc ergo propter hoc" (after that, therefore because of that). Good as heuristics, but bad when they are substitutes for reasoning.
Users cannot diagnose at all because they have no idea of how the thing they are using works (which often normal - we are the engineers, they are the users) (in this regard, users that think they know "that stuff" are among the most difficult to deal with). One cannot properly diagnose something one doesn't understand well.
My wife's car right now is low on windshield wiper fluid. It warns us at a particular spot while we are driving. Not a particular distance from home, a specific geolocation. First thoughts were that it was the amount of time as she went to something and came back. But it does the on screen and audible warning at that location every time, no matter what was driven before that, whether it was 5 minutes, 5 miles, an hour, or 60 miles. The only additional clue is that exact same spot is a dead zone for most phones/carriers.
We got the wiper fluid filled, so the mystery is in remission, but I'm wondering if all warnings will pop up right then. I'm guessing it has something to do with the telemetry of the car being nudged in that spot, waking up and saying something.
Absolutely flat. There is a mild bend there, but nothing compared to corners and the traffic circle. For that matter, we can get out and drive all afternoon and it said nothing until that spot.
I have a similar situation but in my case it's very obviously the gentle bend in that location combined with the relatively high speed that makes the fluid hug one side of the reservoir. I'm pretty sure that the sensor is mounted to the opposite side.
Sounds like an area with strong EM interference. Maybe a stop-light with those underground sensors? or under a high-power line? or near a power transfer station? or high-power radio antennae?
Could be giving just enough weird EM interference to bump the sensor from "enough fluid" to "low"
(I know I sound like Scully from x-files but could just be?)
Experiencing this same issue acutually these days on a 2019 VW Passat, it triggers when you accelerate or break or you are doing a turn for a longer period. It's just the fluid being moved around in the container. I think today I cleaned my windshield for a bit just to make the car keep the low signal light always on.
Long slow bend on completely flat road, 40mph. No braking or acceleration for a quarter mile each direction.
The road is like that for miles with some lights, traffic circles, etc... Only warnings in one spot.
I really didn't believe my wife, or thought maybe it was happening a few times when she made a regular trip like getting drive thru coffee and coming right back. But then we ran a bunch of errands all afternoon and got one warning there on the way out, and one warning on the way back.
My thoughts too. I would often induce a quick g-force to get the last few drops out of the same fluid tank. I could see the same triggering a sensor under similar circumstances.
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On some days it would work perfectly all day long, but on others it would stop working between those hours.
The biggest clue was it would always work perfectly on overcast days, but on sunny days this strange behaviour would manifest again.
Turns out the problem was related to the mouse being a cheap mouse. The case had very thin plastic.
The mouse was a ball mouse, and it worked by shining an LED into a sensor on each of the X and Y axes. On sunny days the sun would completely overpower the sensor due to the plastic case being very thin and on overcast days it would not. On sunny days the mouse would only work when the sun had moved around the sky to cast a shadow over where the mouse was being used.
Perfectly logical but baffling at first.
Turns out some versions of the Pangu jailbreak for iOS 7.1.x would crash during boot if the reading from the ambient light sensor was below some threshold. To this day I don't know the exact explanation of this bug, but it seems that Pangu included some unnecessary code that messed with the light sensor [1].
If you don't believe me, there is a huge reddit thread[2] with a lot of people confirming this.
[1] https://www.reddit.com/r/jailbreak/comments/294wob/jailbreak... [2] https://www.reddit.com/294wob/
Called the cable company, tech came out. Everything inside was fine, but the cable from the main line to the house had a tiny cut in one spot, not enough to really affect the connection, but enough for ambient moisture to work its way in and foul the connection.
The other common denominator was the cable company refusing to believe it was an issue with their equipment; this meant it took a couple of months of calling them every night until they finally sent a technician and a manager to my house to verify that I wasn't wrong, leaving my house, coming back 15 minutes later to say "it'll be fixed tomorrow, there's a problem with the LE balance up the road" - and then the issue is resolved.
Now this doesn't sound so bad, until you learn that the first time this happened to me, i had only VoIP - so the internet would start to foul, i'd call the cable company, and the tier 1 would reset my modem at some point, and then i wouldn't be able to call back until after midnight (or whatever), when there was no longer a problem. So after a week of this, i would walk 30 minutes - one way - to a pay phone (remember those?) once the internet slowed, call them, explain that i couldn't do anything they wanted me to do physically, since they disconnected my phone line every time i called.
This is what happens with a de facto monopoly.
I will never pay suddenlink another dime, even if they're the only terrestrial provider, for whatever reason.
A customer's DSL connection dysfunction's frequency increased mornings and evenings. Culprit: the lift's electric motor leaking EM all over the place.
A bunch of DSL connections degrade when traffic increase... Crosstalk in big cables of course !
The sort of fun incidents that take a good while to troubleshoot... I'm glad we are migrating away from DSL to fiber: either it works or not !
They have all the data available on their end, as far as I can tell! (Unless DOCSIS modems somehow don't have a standard "signal receive report" functionality?)
Tech showed up around noon, saw I was indeed having a bad connection, went and checked the signal at the junction box for the street (can't remember what you call these) and everything was normal there, so he closed it back up again and double checks the signal at the house again, but it was fine. He walks the lines to double check but everything looked normal.
His best guess was that moisture was condensing ever so slightly inside the junction box that morning, and was let out as soon as he opened it at around noon, which fixed the problem.
Eventually I called so many times and had so many appointments, that the tech lead gave me his direct number and told me to call him directly the next time it happened. When it did, I did, and he ran some tests, and confirmed there was a problem. I don't know that we ever got it sorted out (it was a while ago), but just getting them to agree there was an issue took a very long process.
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There's an infrared beam and sensor. When the ice tray is full, it is supposed to block the beam, and then the machine stops making ice.
On a sunny day, there's enough bright light in our kitchen to fool the sensor so it keeps making ice.
We have a random magazine that we put on top of it to make it work correctly.
Same sort of problem. The obstruction sensor at the bottom of the door is confused by the strong sunlight and the door stops closing part way and re-opens.
I've tried a toilet-paper tube around the sensor but that isn't always successful. I really wish there was a laser sensor to replace it with.
One day we started having flaky tests, seemingly out of nowhere. We quickly identified that the issue affected tests involving graphical X client applications, but then we struggled to make further progress. The issue was just impossible to reproduce in other conditions... Well, as it happens, the CI jobs were running on some desktop machines we had installed somewhere within our premises. It turned out that some gentleman had plugged a mouse into one of the machines, and left it lying around on the shelf. Since then, when one of the machines was under a heavy load, the fans would spin faster, causing more vibrations, in turn causing the mouse to move, ever so slightly. And for ungodly reasons, this had side effects on tests.
Fun fact: the machines were not on my site, I managed to diagnose this over SSH. I was quite proud :-)
Let me guess - tests with very tight timings?
It turns out our solar panels (or the optimizers, or the inverter) emit radio frequencies that interfere with our garage door opener. When the sun is out and they are producing energy, the interference is stronger than the homelink garage door opener.
A few years ago the garage door openers started working fine. It took a few days to realize it was because the inverter had failed.
I’m fairly certain there are some FCC regulations that would require our installer to fix it, but that relationship soured during installation and I’d rather deal with an unusable garage remote than dealing with them for warranty work.
If you have any amateur radio neighbours they'd probably love to help you with a project like this.
- Use to fix PCs professionally in the early 90s.
- Guy comes in with PC. Right-mouse button stopped working.
- Replace mouse. Still not working.
- Play with Windows 3.1 drivers. Nothing helps.
- Pull HDD from another PC, install, boot. Mouse button still broken. WTF.
- Pull whole mobo, put another spare mobo in, with replacement HDD and replacement mouse. Still don't work.
- Replace PSU. Right-button works.
- Give up on computers, live in wilderness, eat squirrels.
The first was a VDSL connection I had at home. It worked great (fast, for the time) except when it didn't. It always failed in the evening. Techs would come out, bless it as being good, and leave -- because of course it worked while they were there. Unless they showed up and it was broken and then they'd declare that it was an outside problem, and that they'd have to get someone else to fix it (because the residential techs can't do overhead work).
I made lots of (very polite) phone calls, which results in more refunds and more service calls. More than once, my driveway and the street in front of my house looked like an AT&T convention.
This went on for months.
I had direct numbers and emails for tier 3 support and the local manager who oversaw this plant. We were all getting to know eachother too well, and there were boots on the ground addressing this problem as many as three times in week.
I eventually noticed that as the days got shorter so did the evening outages...and that if it was a cloudy day, then that day was often outage-free.
I had an epiphany: The problem might correlate with the angle of the sun, and the duration of exposure!
I checked my logs and the past weather, and sure enough: It lined up.
So I reported my findings, even though they seemed like nonsense as the words came out of my mouth, and they sent out some crazy-haired guy with bluejeans and an untucked shirt who was clearly not used to wearing a uniform, and who was also obviously not normally customer-facing.
"I know exactly why they can't find the problem," he said after I reiterated what I'd learned. "Your neighborhood still has old lead-sheathed overhead lines, and nobody knows how to work on that anymore."
"But I'm certified on that. I'm going to go back to the shop, pick up a bucket truck and get your line fixed. It will take me most of a day to do this, but I will be back when I'm done."
And it was getting pretty late, but he did come back to let me know that he found some things and fixed them. And I don't know what those things were, but it was fine after that -- and it stayed fine.
Thermal expansion letting cosmic rays leak into copper pairs wrapped in paper, tar, and lead? Who knows. I certainly don't know.
I've never encountered that stuff professionally (and it isn't your grandfather's 25-pair cable) and as this dude said, "nobody knows how to work on that anymore."
On some days, exclusively in the morning hours, the printer would fail to detect the start of a new label, printing over several labels.
After connecting remotely and checking the usual (queue, network connection, drivers etc), I asked my colleague to call me, as soon as it happened again.
When I went there, I saw that a ray of sunlight hit the printer. The windows had shutters, but there was a gap.
Label printers detect the gap between labels using a laser. And for some reason, the printer's case had a clear window at the top.
I printed an empty label and stuck it on the little window.
I would have guessed they'd shrug at the first sign of trouble, swap it out with a known-working mouse and mark the ticket resolved... unless all the replacement mice were thin plastic too, I suppose.
It would bother me until I figured something out.
https://web.mit.edu/jemorris/humor/500-miles
Seriously, this is one of those dumbass stories that come from your boomer relatives with the subject line "fwd: fwd: fwd: fwd: fwd: fwd: fwd: fwd: re: fwd: fwd: fwd: fwd: fwd: fwd: vanilla ice cream"
Nobody actually believes this story is true, right?
In fact, I'd argue the quaint style of the story does geeks a favor: if it's appealing to normies, maybe they'll appreciate us technical folks' perspective a little more.
And the engineer is sitting in the car on the first night and it "wouldn't start," which signals the end of the episode for the day. Were they stranded? Did the car start after a few tries, which would have given a huge hint about the root cause? Surely the engineer who had reproduced the issue would quickly narrow it down by running diagnoses on the car itself.
But the family dynamics are the most improbable part here. How does the family have this predictable routine and not simply stock up on ice cream? The family has enough kids that the consume a whole $unit of ice cream per day. So with that much chaos in the house, how does the dad justify going out for a drive after dinner when the chaos of family multi-tasking (cleanup, chores, homework, bedtime) is at its peak? "Oh, look. Out of ice cream again. I'll be back in a few!"
They still work perfectly... except for a regular pop of noise every few seconds that would intermittently show up, that scaled with the volume setting.
It turned out, their portable phone (read: landline with short-distance wireless RF handset) would ping from the base station to the handset, if it were off the cradle, which was being picked up by the unshielded line-level audio cable and amplified.
Moved the base station further from the cable, pop disappeared.
We were developing a smart camera product which were counting traffic on a road. So for example a city council would install this camera somewhere on a road and it would generate statistics of how many lorries, and passenger vehicles, and motorbikes used that road.
One of our cameras exhibited a problem where it restarted every day around roughly the same time. It wasn't exactly the same second though, in fact there was a clear pattern to it. One day it would restart at 19:12:10 and the next day two second later, then again the third day two more seconds later. (not the real timestamp and i don't remember the real time deltas either, but there was a clear progression)
After much debuging we learned that the issue was that as the sun was settling some street furniture projected a shadow in front of our camera. Our software wrongly concluded that it is a vehicle and started collecting information about it for classification. But of course shadows creep a lot slower than real vehicles so it run out of memory before the "shaddow vehicle" has passed out of the frame. And once we run out of memory the system froze and then got restarted by a watchdog.
Turns out the pattern we have seen in the timestamps was caused by the angle of the sun changing which made the shadow trick our algorithm just a little bit later every day.
[0] https://old.reddit.com/r/talesfromtechsupport/comments/5yrs1...
[1] https://www.goodreads.com/book/show/3227607-the-devouring-fu...
0. https://www.cnn.com/2023/06/27/us/janitor-alarm-freezer-rens...
1. http://www.st-v-sw.net/Obsidian/Martin/gravity.htm (search sprinkler)
The ice cream story reads too much like a dramatisation to be truly believable, but accidental and repeated unplugging is common I expect.
The UPS on a server I manage would trip once a week around the same time. The old story came to mind and sure enough, once a week it was time to vacuum and someone would plug in a vacuum cleaner into the same circuit (700W vacuum cleaner on a 100V/15A circuit), causing enough voltage dip to kick the UPS into gear.
Sorry but even before today, having a automotive engineer sent to a random person's home over what clearly sounds like a quack letter seems implausible to me. The dictates of capitalism, human resources, and the politics of the workplace would make this difficult if not impossible. Even in the past when there was more human capital in support positions and more of a sense of customer service.
Way, way too many suspicious stories involve high-level people being involved in trivial issues. I just find it all pretty suspicious. Real stories tend to start with poor customer service at the dealership and being mocked by managers and mechanics. Not some unrealistic ideal white knight manager sending off engineers to people's homes. Imagine how many weird letters a place like pontiac gets. They don't have the manpower to do this if they actually chose to do it, and engineers might balk at the idea of doing at-home support too.
Pretty much any "idealized Americana" business story should set off BS alarms in us. "Oh a trivial problem with your car? No problem ma'am, I'm sending our top engineers over tomorrow," doesn't happen because its costly and unsustainable. Instead ask anyone who has odd car problems. Its endless painful calls and visits to dealerships and mechanics. There's a reason we have lemon laws for cars. Its because whats described in this story doesn't actually happen and people demand restitution.
I don't doubt that someone had a famous vapor lock shopping story (ive heard different versions of this story, usually about a housewife picking up her child from a nearby elementary school), but over the years these stories get modified into memetic structures based on dishonesty because most people are social capital seeking and having a humorous story provides them the immature ego boost they need. So "wow my car had vapor lock when I make quick trips" became "So the CEO of Ford came to my house to look at my ice cream car..." The latter is just more interesting in the market of storytelling.
That is to say, the ONLY reason this story is here is because its been modified to be memeticly attractive. A "boring" (i find old technology faults interesting, personally), but a "boring" story about vapor lock wouldn't make it to places like HN or reddit, which are memetic responders (upvote/downvote mechanisms) and lowest-common denominator (by this demographic) popularity machines. But dress up that boring story and now everyone is repeating it, often times claiming its their story and they know the people in it! The same way the comment you're responding to probably doesn't actually know the famous "unplug the server at 5pm" person.
It turned out that the lawyer next door would come in, turn on his PC, printer and coffee pot simultaneously because they were all on the same power strip, and the drain was causing an undervoltage on the circuit the server was on during startup. We had it on a UPS, but it turns out that at the time consumer grade UPS systems only handled outages.
I measured drops as low as to 85 volts, in practice anything under 95 or sou would reboot.
less than an hour later, we get an email from nagios (i think it was nagios? it was a GOOD while back) complaining the server was offline. we got into a cab and went back straight up (this server was not supposed to be offline ever).
guess what? a maintenance guy turned the server off by mistake while cleaning up the server room -- even worse, he was not even supposed to be there!
this triggered a bunch of security checks and the company found out that most employees had access to any room in the building.
The hardware consisted of 6 color terminals (Wyse 350s I think), the server, and 10 PCs with large, 20” tube monitors. We had these all in my bosses office powered through assorted outlets and power strips. The room was wall to wall machinery.
It was after hours when the janitor came in and plugged in his vacuum. I looked at him, he looked at me, I looked at my boss, who looked back. We then both turned back to the janitor, who looked at us.
Not a word was said as he fired it up. 2 seconds later, the power was out, we blew the breaker. Took us a half hour to get it back on. But it was funny at the time.
Huh? Yesterday? Or are you referring to the fact that servers are now often offsite, in 'clouds'?
Brother-in-law was known to be "not so good" with cars - so his automotive engineer father didn't take the complaints seriously.
Complaints and emotions escalated, until brother-in-law convinced his dad to swap vehicles for a month, so (he hoped) his dad could experience the problem for himself.
After the problem manifested in the parking lot of the GM Technical Center, and the whole crowd of GM engineers surrounding the vehicle couldn't figure out why the heck the electrical system seemed to be dead, my brother-in-law felt pretty vindicated.
Had it towed to a service center a few times when this happened. Every time, by the time they got around to trying it (a few hours later)... it would start fine, with nothing to diagnose.
Then, it was 99% of the time it was fine. I was with a group of folks car-camping off road to fly a human powered airplane for a couple days, and... no start. Finally started -- with no sign of any problems -- around noon the next day, and I high-tailed it out of there a day before the rest of the group, because getting stuck there /after/ the rest of the group would have started pushing my comfort level. So at this point it's actually interfering with my life.
I've tried all the usual stochastic troubleshooting (swapping out fuses, light to moderate percussive maintenance, alternate keys) and nothing. Finally it fails to start in my driveway, and I get it towed to an independent mechanic. It's short tow, and it fails to start when it gets there! So now he's seen the problem, and is as puzzled as I am. Of course, when he tries again the next morning, it starts fine.
He proposes two possible fixes: replacing some ECU module, or replacing the fuse box itself (under the theory that it's the connector or connection into the bottom of the fuse box that is having some moisture ingress or intermittent connection). Of course whatever we choose, I won't know if it was right or not until the next time I'm stuck. The ECU is multiple thousands of dollars, and the fuse box is < $200 with labor, so I make the easy choice.
This was six or seven years ago, and that car is still my main and only car. Hasn't had a single mechanical issue since swapping out that fuse box. A good independent mechanic and a good guess!
Finally figured it out after months when I moved a wire and it started, then move the wire close to another wire and it would no longer start. These were wires that would typically be close, so my guess is one of the wires was now generating enough noise that it was bleeding over into some other system and causing it to fail. As the car bounced around the proximity of the wires changed and lead to the random behavior.
I know an older guy at church, whose kids all graduated college - except for one.
His "failed" son is the top mechanic at a Mercedes dealership. He does some supervision, training, etc. But the reason the dealership is paying him $200K/year is his skill at figuring out and fixing problems like that, for the dealership's most desirable and profitable customers.
(That I've heard, none of the mechanic's "successful" siblings are making that kind of money.)
The easiest diagnosis is to rotate the cables on the terminal several times to rub off oxide build up, then leave them in an orientation so that the natural tension of the cable forces the clamp into good contact.
A "dead" (low voltage) battery will still cause some indicators/lights to come on when you crank, while a bad connection usually acts like zero volts.
The car was dead for long enough that I could get it towed to the mechanic and they educed it was a problem with the EIS (electronic ignition system).
The EIS computer was sent off to mercedes for diagnosis, they reported that the computer itself was fine but it was an issue with power. The mechanics traced it back to a bad connection of a wire somewhere.
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That GM vehicles from this infamous era would suffer from maddening, mysterious electrical glitches makes perfect sense.
Mechanically they may be reliable, but 90’s GM forgot how to make paint stick to metal and had to pay to repaint a massive number of vehicles that simply pealed if parked outside for too long. How?
And there is absolutely no forgiveness in my soul for the Chevy Citation. I joked when I moved to Seattle that the main problem is since there is no salt, there are still Citations on the road and that is unnatural. Their place in the natural order is the junk yard.
American carmakers really needed that kick in the ass from Japan. Around 1990 was when my parents went from being protectionist, "buy American" to never buying another domestic car again in their lives. They were angry, angry at the reliability difference and angry knowing that domestic carmakers could have done better but instead relied on people like them to buy the flag.
Like turning on the backup lights in a parking lot when the engine isn't even running.
On Consumer Reports' list of car brands by reliability[0], none of GM's brands even crack the top 10. GMC and Chevy are 20 and 21, respectively, out of 25 brands. (The top 5 include, unsurprisingly, Toyota, Lexus, and Honda—your classic reliable Japanese brands.)
[0] https://www.consumerreports.org/cars/car-reliability-owner-s... (may be paywalled...?)
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It's been long enough that I don't remember what I did to get it shut off (maybe I toggled a circuit breaker?), but when I got back to base, I made a note in the airplane log about the problem and also left a note for my instructor, who was out that day.
When I came in for my next lesson, instructor mentioned that the next person to use the airplane, also a student on a solo cross-country, got stranded 100 miles away because when the engine wouldn't shut off, he panicked and pulled the throttle hard enough to rip the cable through the firewall. Airplane had to be put on a flatbed to get it back home.
Guess he didn't see my note!
I just tapped the relay with a wrench and it un-stuck and turned off.
Funny enough that was almost 5 years ago, and it hasn't done it once since in more than 80,000 miles of driving. Not in -35C, not in +45C. Odd little relay.
My (GM) car gets really funky startup behavior when the battery gets old. It will often turn the starter fine, but the electronics can get stuck in weird states until I disconnect the battery (essentially a hard reset).
https://www.subarubatterysettlement.com/
The dealers wanted a ton of money to diagnose the issue, even though I suspected it must have been the infotainment system draining the battery. I just ended up replacing the infotainment system with a cheap CarPlay compatible one and the problem went away.
Problem is I cannot get money from the class action settlement since the original infotainment system is already out and I fixed it myself.
In that house,on certain days of the week at midnight, something that sounded like recordings of political speeches from WW2 would be audibly (but faintly so) from all of stationary electronics. It was so faint, that it was usually hard to pinpoint any one source, and the words used weren't understandable, so it usually sounded like it was coming from everywhere all at once, and like it was an old recording.
This would happen even if they were unplugged. Even if my power went out.
I though I was either going crazy, or my house was literally haunted by hitlers ghost.
Well one day I was in my car and recognized something on the radio that reminded me of this spooky problem I had.
It was the signon of a Catholic am radio station that opened up with Gregorian chanting, and a sermon. This signon happened at the same time on the same days of every week.
Turns out, the wiring in that house was somehow functioning as an am radio receiver, and some common components would vibrate out the audio encoded in the radio signal.
A pair of old not-plugged-in computer speakers can also be an AM radio receiver.
Source: http://telecom.csail.mit.edu/judy-sammel.html
Every time I played on his laptop, this did not happen. He swore he was cursed.
This went on for many days, with many instances where it would happen for him but not for me. Then one day I just sat and observed him while he played, looking for any difference. That's when I noticed his watch band is metal with a magnetic clasp. The position of his wrist on the laptop was tripping the hall sensor, making the laptop think the lid was closed.
Him and I (and his mother) were glad to find out he is not cursed. :-D
https://www.ifixit.com/News/33952/apple-put-a-hinge-sensor-i...
word to the wise - never use the shutoff switch on anything with a carburetor - use the fuel shutoff valve. This prevents gasoline from varnishing your carburetor bowl.
I probably won't use that word again for a year, now, heavens.
I'm absolutely a car guy, and I'm 41 years old.
Strangely enough, I've never owned a carburettored engine, and it seems unlikely I ever will (except, maybe, for a chainsaw)
To me the moral of the story (and my experience) is: user's problems are usually real, but don't trust their ability to diagnose the actual cause.
Proximate cause: buy vanilla ice-cream
Root cause: vapor lock
The letter didn't assert that the ice cream was the root cause, but made it very clear it was the proximate cause.
The Pontiac President, and the person who wrote that "moral of the story", may have confused the two. But the engineer in the study didn't.
I used to do some help desk as part of my dev job, and from my experience, users easily assign any random fact as the source of the problem. Often things like "correlation is causation" or *post hoc ergo propter hoc" (after that, therefore because of that). Good as heuristics, but bad when they are substitutes for reasoning.
Users cannot diagnose at all because they have no idea of how the thing they are using works (which often normal - we are the engineers, they are the users) (in this regard, users that think they know "that stuff" are among the most difficult to deal with). One cannot properly diagnose something one doesn't understand well.
We got the wiper fluid filled, so the mystery is in remission, but I'm wondering if all warnings will pop up right then. I'm guessing it has something to do with the telemetry of the car being nudged in that spot, waking up and saying something.
Could be giving just enough weird EM interference to bump the sensor from "enough fluid" to "low"
(I know I sound like Scully from x-files but could just be?)
The road is like that for miles with some lights, traffic circles, etc... Only warnings in one spot.
I really didn't believe my wife, or thought maybe it was happening a few times when she made a regular trip like getting drive thru coffee and coming right back. But then we ran a bunch of errands all afternoon and got one warning there on the way out, and one warning on the way back.