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I fixed a parasitic drain on my car in 408 days

davidmuller.github.io

331–340 of 515 posts

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

#331

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Tangent, but what's the rationale for car doors requiring slams? They are the only door I know, at least in common, daily life contexts, that require slamming them with the force of Thor to properly close them.

I think one of the reasons is air pressure inside the car. I've always found it amazing how much less slamming the doors needed when a window was left wide open and the air inside the car could escape freely.

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

#332
post #325

Well this is timely. I have a parasitic draw on my NC Miata. The first mechanic just replaced the battery. The second told me it's normal for the battery to die if you don't drive it for 3 days (because "cars have computers now"). It seems like mechanics really don't like digging into the electrical part of the car... but these days that encompasses more and more of what can go wrong. Without time to dig into it myse…

I solved one recently. Really wish there was a simple time logging multimeter that you could leave plugged in 24 hours.

Most cheap multimeters have an ir or similar data port you can use for that.

Just need to hold a button when turning on the meter to disable the auto power of timer, then you run software on a laptop to log the data to csv

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

#333
post #101
post #94

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If you like watching amateur YouTubers rip out their hair chasing electrical problems, I recommend checking out Tavarish and Samcrac. It turns out cheap flooded auction cars have tons of those

Pine Hollow Auto Diagnostics South Main Auto Watch Wes Work musty1

And if to want to see an actual professional, diagnose dan

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

#334
post #267

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That's fair, but it's funny because that's how I always felt about BMWs. My buddy loves them but I always felt like they were so... sterile. Unless you are at a track or love cutting off people in traffic it feels really hard to have any fun in one.

Agreed - the last 5 that felt good to drive was the e39, and the rest probably peaked with the e90 or e8x. I felt the same way with the corvette - my c5 was the most fun to drive. C6 was an upgrade in comfort but significantly number, and the C7 was horrific. I took a C7Z for a spin and it felt slower and more boring than my c5 despite having 2x the HP.

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

#335

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Thats insane... To consistently not close the door like that

My wife, bless her heart, leaves everything partially open. Not even just open, but she'll screw the lid on jars just enough where if I pick it up by the top they'll drop. It drives me crazy.

That should be a felony

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

#336
post #219
post #62

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The problem with specializing in these issues is that most customers will be dissatisfied when you charge them thousands of dollars to reset a minor module on their car. How many hours of shop time are you willing to pay for with no guarantee of a solution, and very few (if any) parts replaced?

> How many hours of shop time are you willing to pay for with no guarantee of a solution, and very few (if any) parts replaced? Imagine opening a computer software support business where you bring in your old proprietary binary programs that you got from who knows where, and the business is to fix bugs you've found. Maybe some really big enterprises would pay for that sort of thing. But I doubt it would be feasible f…

There are companies around that offer VIN re-coding by mail order if you need to swap one of the computers, but you'd have to be in a fairly big metro area to profitably run a company just doing electronic trouble shooting. It's easier just to "fire the parts cannon" after the usual suspects (dead sensors, shorted wiring) have been accounted for.

Having had a 2006 model car in my workshop forever rebuilding the engine, I have though it might be worthwhile starting a business doing that kind of trouble shooting but nobody will want to pay, because the vehicles involved are inevitably old and worthless. It's fun to do it for yourself, but as a business your typical customer who needs you won't be able to justify paying you.

My other thought was to possibly set up the tools and whatnot to support local businesses in doing that kind of troubleshooting on older cars but building the knowledge and tools to distribute would be a very expensive exercise.

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

#337

I’ve been wondering if my old HOUSE has parasitic electrical currents but I’m not sure where to start.

There are devices you can get to monitor each one of the circuits from the breaker panel like https://www.amazon.com/Emporia-Monitor-Circuit-Electricity-M... . This would let you narrow it down to a specific circuit. Figuring out what's connected to that circuit and actually taking up the power might be more difficult.

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

#338

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Well that's dumb. I've never heard of that before. But I guess I shouldn't be surprised. Thanks!

It gets even more fiendish than that - you can have entire linked dependencies of locked modules. My old Saab’s key was locked to the security computer, to the column immobilizer, then to the engine computer. Lost one key? Bummer. Lost all your keys? $2500, several hours of reprogramming time at the dealer, and a bunch of new parts shipped over from Trollhattan. Thankfully the hacking scene has managed to bypass lots…

It's going to get worse - on most cars the CAN bus is not encrypted and the messages are not signed. There was a comment here recently where a tech in the auto industry claimed that one manufacturer was planning to start signing the CAN bus packets. That will mean it likely becomes impossible to do things like re-code the PCM for a motor with a different VIN so you can re-use the PCM in another vehicle.

That will be quite hard to overcome.

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

#339

Earlier quoted context omitted.

With my car, trying to lock the doors just doesn't work if one is left open — not always the most obvious failure mode, but it's been enough to get me to notice something's wrong.

> With my car, trying to lock the doors just doesn't work if one is left open for suburban single family residence dwellers with their own garage, they may not always (or ever) lock the doors while the car is parked in their locked garage.

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

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

#340

Earlier quoted context omitted.

> 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’…

Yes. I had a problem with a leaking transmission once and the shop refused to accept my diagnosis because "in all my years servicing transmissions, I never heard of that failing." Finally, the service manager agreed to check it out with the understanding that if I was wrong, I still had to pay for the time they spent investigating. I was right :-)

Debugging spider sense is definitely an upside of spending years working with terrible code.

I once moved into a place that was great, except the shower would start out hot, quickly drop to warm, and then stay warm for as long as we cared to try it. I hated this, so every time I showered I'd spend some time trying to debug it, despite knowing nothing about plumbing.

Eventually I asked myself: why do normal hot water heaters work the other way, where they stay hot a long time and then get pretty cold? Clearly, there's some way of keeping the incoming cold water separate from the already-heated hot water, like by putting the output pipe at the top and the input pipe at the bottom. But if you reverse them, you might get what we had.

I leapt out of the shower and felt the hot water heater pipes and sure enough, reversed. My landlord came over shortly thereafter and fixed it, and I felt very smug when I had my first properly hot shower.

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