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Car allergic to vanilla ice cream (2000)

cs.cmu.edu

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Re: Car allergic to vanilla ice cream (2000)

#141

Post by MarkusWandel »

Someone in my extended family had a Toyota Highlander which would randomly decide "you don't need window defog today", leading to a near inability to drive the car if fogging was an issue. The dealer didn't believe him until one day it actually happened while they were watching. They had no idea what to do or how to fix it. Solution: Trade the thing in against a Honda Passport. He's had that for quite a while now and I haven't heard any complaints.

On the other hand, my previous Honda Civic with its dual voltage electric system (computer thinks the battery needs charging? Generate 14.4V. Computer thinks it doesn't? Generate 12.6V) caused us considerable grief until we just started driving around with the headlight switch on all the time (this forced it into the higher charging voltage). This "feature" is not well known/understood even by mechanics and has probably caused untold numbers of alternator replacements.

Current Civic is so automated that even the headlight on and high/low beam is under the computer's control. Hopefully no weird chronic computer bugs in this one.

Re: Car allergic to vanilla ice cream (2000)

#142

Post by shadowgovt »

I currently have a Raspberry Pi that consistently loses its network stack at some point in the early morning.

The likeliest correlation is that I have the Pi dump backups at that time, and it may be crashing the network stack due to unexpected hardware output because running a hard drive and the internal wifi simultaneously under-volts the system. But it sure does look like it just gets visited by demons in the pre-twilight hours.

Re: Car allergic to vanilla ice cream (2000)

#143

Post by bbarn »

amluto wrote: post #110
LanceH wrote: post #67

Earlier quoted context omitted.

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…

> Long slow bend That’s probably it. If I were designing a wiper fluid warning, I would use some sort of fluid level sensor and I would denounce it aggressively: the indicator would only light up if the sensor detected a low level for more than a couple seconds. That way traffic circles, bumps, etc would not cause many false positives. I might even couple it to some kind of acceleration sensor so a warning would not…

The question then is does it only happen in one direction? If the answer is yes, than I think you've solved it. If the answer is no, it might still be the problem but the sensor might be top or bottom mounted and not side mounted from the center I suppose.

Re: Car allergic to vanilla ice cream (2000)

#144

Post by m463 »

MalcolmDwyer wrote: post #133
jjbinx007 wrote: post #49

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…

We have a countertop ice maker that gets jammed up and overloaded with ice on sunny days for a similar reason. 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 cor…

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.

Re: Car allergic to vanilla ice cream (2000)

#145

Post by schainks »

One night while in the computer science lab doing a Java assignment, my professor for that class happened to walk by the lab and quipped to me, "oh, good luck on _that_ machine."

He explained: once upon a time, the machine refused to run _any_ Java programs, and would spectacularly crash and burn instead. C++ fine, python fine, anything Java was a hard nope. He didn't believe this at first until his program also started crashing the machine.

It took a tech, him, and another professor about two weeks to work out that the JVM happened to allocate the same RAM address to the integer 12 on that particular machine every time the JVM started. The actual chip of RAM that contained that hardware address was faulty, so whenever the machine tried to allocate to that address, it would crash.

Swapping out the bad RAM stick immediately solved the problem.

Re: Car allergic to vanilla ice cream (2000)

#146

Post by timmorgan »

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

Re: Car allergic to vanilla ice cream (2000)

#147

Post by freedomben »

addaon wrote: post #40
bell-cot wrote: post #2

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 serious…

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 h…

What happened with the human-powered airplane?? Is that a thing normies can do?

Re: Car allergic to vanilla ice cream (2000)

#148

Post by asddubs »

jjbinx007 wrote: post #49

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…

Another similar anecdote I heard before was related to a wireless device, and some employees flying a drone during their break, generating interference.

Re: Car allergic to vanilla ice cream (2000)

#149

Post by kup0 »

This reminds me of the "my monitor blinks every time I sit down in my office chair" turning out to be EMI spikes from the gas lift affecting the signal traveling on monitor cables.

A DisplayLink KB article even mentions it (and the associated white paper about the issue), stating:

Surprisingly, we have also seen this issue connected to gas lift office chairs. When people stand or sit on gas lift chairs, they can generate an EMI spike which is picked up on the video cables, causing a loss of sync. If you have users complaining about displays randomly flickering it could actually be connected to people sitting on gas lift chairs. Again swapping video cables, especially for ones with magnetic ferrite ring on the cable, can eliminate this problem. There is even a white paper about this issue.

Re: Car allergic to vanilla ice cream (2000)

#150

Post by tantalor »

maweaver wrote: post #34

> Moral of the story: even insane-looking problems are sometimes real. 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.

There's a big difference between the proximate cause and root 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.

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