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I fixed a parasitic drain on my car in 408 days

davidmuller.github.io

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Re: I fixed a parasitic drain on my car in 408 days

#441

Post by jimnotgym »

gonehome wrote: post #329
jimnotgym wrote: post #264

Earlier quoted context omitted.

Good luck in 5 more years when Tesla decide that your car is now unsupported. I wonder if the Tesla mechanics are measurably better than the franchise dealers? I doubt it. I bet they have fancy testers, but when the tester is not showing 100% the right answer I doubt they are any use at all.

I've had mine (Model 3) for about 5 years now, so far they updated the hardware for free and it's gotten way better software for free over the air. It's a much better car now then when I bought it (so at least so far, the opposite of what you suspect is true). Service has also been way better for me than when I had cars serviced by franchised dealers, but that may be because I'm in SF. I had an issue and two days lat…

I said. Good luck in 5 more years when Tesla decide that your car is now unsupported.

>Service has also been way better for me than when I had cars serviced by franchised dealers

Which franchised electric car dealer are you comparing it to?

Re: I fixed a parasitic drain on my car in 408 days

#442

Post by benhurmarcel »

sokoloff wrote: post #106
lylejantzi3rd wrote: post #28

Earlier quoted context omitted.

> It seems like mechanics really don't like digging into the electrical part of the car... Tell me about it. I'm in a similar boat. My audi a4 has had a parasitic draw for the past 10 years. My mechanic didn't want to take the time to address it because that sort of thing takes a serious amount of time and he's always backed up. I got out my fluke and narrowed the cause to what I believe is the comfort control unit.…

> My mechanic won't do it because he won't confirm that's the cause. My experience is that a lot of independent mechanics will do what you ask them to do, so long as they think it’s not unsafe and have confidence that you’ll pay the bill without complaint when the task is done whether or not the problem is fixed. Probably not a good “this is my first time meeting you, but please replace my flux capacitor” but if you’…

I've done that twice with some shops I didn't have any history with.

Once I got them to replace my gearbox oil even though they said it wasn't needed. With another one I brought them a third-party pedal and asked them to install it. In both cases it did solve my issue by the way, even though I might have been wrong.

They don't care as long as you're ok to pay for the hours regardless of whether it solves your problem or not.

Re: I fixed a parasitic drain on my car in 408 days

#443

Post by chrisdhal »

yurishimo wrote: post #236
chrisdhal wrote: post #121

Earlier quoted context omitted.

My wife drives about once a week, probably less on average. She has a 2013 Honda CR-V, only 15,000 miles on it. We live in Minnesota, so have cold temps, but the car in a garage. The car always starts. We've replaced the battery once just due to longevity. Every 3 days? No way.

15k miles on a 2013 CR-V? Enjoy the last car you'll ever own! I assume you know this, but some of the maintenance items for that car are 8 years I think; worth checking the manual to find out!

Haha, yep. She refers to it as the literal "just driven to the grocery store by a little old lady" car (because it's basically that and Home Depot). She even got the lowest trim level (on purpose) so it doesn't have anything fancy (no BT radio, no keyless start, no big display, etc.).

Good point on the maintenance. I do get the oil changed, again more by time than distance, and I'll look up the other stuff now that you've mentioned it, thanks.

Re: I fixed a parasitic drain on my car in 408 days

#444

Post by ljf »

bityard wrote: post #171

One thing I haven't seen mentioned yet: If your battery is dying way sooner than it should be, and if you have _any_ aftermarket equipment installed (radio, backup cam, alarm, remote start, trailer light module), that should always be the VERY first thing to suspect. These things are not engineered to the same requirements as the OEM electronics, and if they are drawing 10s of milliamps while the car is off, that is…

This is exactly what happened to my car - I fitted a reversing sensor (this was some time ago).

About a month later the battery was flat - but we didn't drive that often so I thought it might be that. Charged it and was fine for another month or so, but then it started to happen more and more frequently. I took to disconnecting the battery each time I parked up the car.

It was only when I came to scrap the car (for unrelated issues) and went to remove the reverse sensors to use on another car that I saw a single thread of wire that was running off the reverse light, was causing a short. Ah well - lesson learnt!

Re: I fixed a parasitic drain on my car in 408 days

#446

Post by Nextgrid »

bityard wrote: post #131
jessaustin wrote: post #123

Earlier quoted context omitted.

Pulling fuses is a pretty reliable way to find the relevant fuse in the first place. If the battery doesn't run down while a particular group of fuses is pulled, the one you want to pull is in that group. Start with half the fuses, then narrow down. You might have to reprogram your radio channels...

I can recommend searching for "South Main Auto parasitic draw" on YouTube. The guy is a genius at electrical troubleshooting. His strategy isn't to pull fuses, it's to set the car sit for at least 30 minutes or so (with key off) and then check each fuse with a multimeter to see which has current on it, and then check everything on that circuit. Arm yourself with schematics and wiring diagrams, otherwise it'll end up…

"Pine Hollow Auto Diagnostics" is also a very good source.

Re: I fixed a parasitic drain on my car in 408 days

#447

Post by Reason077 »

hoseja wrote: post #393
Reason077 wrote: post #386

Earlier quoted context omitted.

My flatmate does this with kitchen cupboard doors, and, most annoyingly, the microwave. She'll open the microwave to stop it, takes her food out and, just ... leaves it open. Then when I close it later it will start up again with nothing inside. Arrrgh!

IMO a good thing, lets them ventilate better. Not cancelling the timer is the wrong thing there.

Not sure about that. It's normal to open a microwave periodically to inspect, stir the food etc to ensure it is heating evenly. Automatically cancelling the timer each time you open it would be very annoying.

Re: I fixed a parasitic drain on my car in 408 days

#448

Post by Nextgrid »

ilyt wrote: post #110
rzzzt wrote: post #95

Earlier quoted context omitted.

Ye olde ammeters were secretly voltmeters with a low-value but high-precision shunt resistor in series with the circuit to be measured. Current passing through the resistor causes a tiny voltage drop, which is measured by the meter. As the voltage is proportional to the current, the scale painted on the cardboard behind the needle did the actual conversion. In the author's setup the fuse takes the shunt's place; its…

> Ye olde ammeters were secretly voltmeters with a low-value but high-precision shunt resistor in series with the circuit to be measured. "ye olde"? That's how every typical one works, till you go to clamp meter > its resistance is apparently a known value that can be gathered from a datasheet. that's... optimistic

> that's... optimistic

The absolute current value probably doesn't matter - in fact I very much doubt a hobbyist-level multimeter is even capable of accurately measuring the (fractions of?) millivolts across a fuse.

It's more important as a boolean signal - "is there current being drawn on this fuse?", and then usually even those fractions of millivolts will generally be enough to make your el-cheapo multimeter register 1mV and tell you something is drawing current, where as a fuse with no voltage drop across it at all will reliably show 0mV (just like it would if the probes were shorted) on even a cheap meter.

Re: I fixed a parasitic drain on my car in 408 days

#449

Post by shrx »

lukego wrote: post #422
Reason077 wrote: post #386

Earlier quoted context omitted.

My flatmate does this with kitchen cupboard doors, and, most annoyingly, the microwave. She'll open the microwave to stop it, takes her food out and, just ... leaves it open. Then when I close it later it will start up again with nothing inside. Arrrgh!

I learned this behaviour for a while when living with a microwave that made an annoyingly loud beep when it finished or was stopped. Workaround: slightly ajar as default idle state for silent operation and intercept immediately before completion.

The first time I heard the annoying beeping of my microwave I opened it and cut off the piezo beeper. Have been living in blissful silence ever since.

Re: I fixed a parasitic drain on my car in 408 days

#450

Post by dcormier »

Kirby64 wrote: post #378
WirelessGigabit wrote: post #339

Earlier quoted context omitted.

Which is one of the things one must absolutely do to ensure all modules go to sleep.

No car I'm aware of requires this. If the ignition is off and the doors are all closed, the car is, for all intents and purposes, asleep. If anything, doors unlocked may be lower power... as that would disable (or, rather, not enable) alarm functionality.

The author of the linked article mentions a couple of times to lock the doors for the car to go to sleep properly.
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