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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

#361

Post by wpietri »

breischl wrote: post #358
wpietri wrote: post #340

Earlier quoted context omitted.

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…

I once spent over a year debugging a furnace. It would run fine, except every now and then on it would just refuse to turn on for a day or two. Eventually noticed it was only rainy days, and was due to it thinking the exhaust was blocked because there wasn't enough pressure differential between input air and exhaust. Turned out the installer had failed to put in the high altitude kit which told it to expect a smaller…

Ooh, well spotted. Correlation is correlated with causation!

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

#362

Post by WalterBright »

My experience with car mechanics is they are good with mechanical systems, but have little understanding of anything electrical, and even worse with electronics.

P.S. If you're doing a bit of wiring on the car, don't use those crimp on wire connectors. They'll work ok for a year or so, and then start behaving erratically, slowly getting worse and worse. This is because the crimp is simply not tight enough, and the mating surfaces start to corrode.

The best solution is to strip the wire ends, slip some heatshrink tubing over the wires, cut the plastic off the butt crimpon connector, crimp it on, solder the wires to it, move the shrink tube back over the joint and shrink it on.

This goes for any crimpon connector.

Also, don't use the auto wire you get at your local auto parts store for anything in the engine compartment. It won't last in the heat. You gotta get heat resistant wiring.

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

#363

Post by xyst »

Personal vehicles are getting way too complicated now. Too many electronic components that can be points of failure.

Recently viewed a video on “steer by wire yoke”

https://m.youtube.com/watch?v=agMrewRJTow

It’s very interesting but there are so many additional motors, sensors, and actuators to simulate the same experience as mechanical based steering.

If you lose electronic assistance in traditional mechanical based steering, you have to apply more force as a driver and makes the experience difficult.

What happens if I lose one or more components in this “steer by wire yoke”? Seems like as a driver you are shit out of luck. If you are a pedestrian, bye bye.

All I want is a walkable city with public and alternative forms of transportation. All of these “car innovations” are mostly useless.

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

#364

Post by matheusmoreira »

o10449366 wrote: post #324
adversaryIdiot wrote: post #254

Earlier quoted context omitted.

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.

I've met a lot of women who do stuff like this... I asked one why and she told me it's because they don't want to be a bother. Fully closing the door makes noise, screwing on lids can make it hard for people to open them later. So they don't. They close it just enough and leave the object in that almost there state.

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

#365

Post by KennyBlanken »

garyfirestorm wrote: post #275
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.…

> I can’t replace it myself because it’s a coded part. Can you please explain this? Why does it need ‘coding’? It’s not a VIN specific part I’d think - i.e. engine controller. Also have you explored Ross Tech VCDS tool? You might be able to identify the coding on your part and use it on a new part. Replacing an ecu should be straightforward imo.

In VAG cars, the ECU and dashboard are often paired to each other for anti-theft purposes, since the immobilizer is part of the ECU itself. To stop people from simply pulling the ECU and replacing it with one keyed to the immobilizer key chip they have - the ECU is paired to the dashboard, which often requires a lot more time and effort to remove.

For other modules they're often used across many different cars/engine/transmission/body type and regulatory markets. "Coding" a module tells it what accessories/options it's connected to, what else is in the car, what regulatory market it is in, and so on.

There's also "coding" for how the module behaves with certain features. For example, body control modules on US cars won't allow you to use the remote to roll up the windows, but by flipping one of the coding bits, you can enable it. There's also silly stuff like enabling / disabling gauge sweep on the dash.

(Explaining this mostly for others, you seem aware of at least some of this)

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

#366

Post by Cyphase »

noizejoy wrote: post #305
Dalewyn wrote: post #294

Earlier quoted context omitted.

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.

It's fascinating how doors and windows in a house interact with air pressure. The way doors act when a window is closed versus open, how a half-out-of-frame door will open when a door to the garage on the other end of the house is opened, active central air holding an ajar door against it's frame, etc.

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

#367

Post by somat »

gsich wrote: post #301
tempestn wrote: post #292

Earlier quoted context omitted.

Not to mention more minor annoyances like losing radio stations and other settings.

It's insane that this keeps happening. Computers can remember BIOS settings for probably 40+ years now.

They use a battery backup. The main symptom of having a dead cmos battery is that your computer starts loosing it's cmos settings, it's a feature not a bug. I have a system where it keeps the cmos config on flash. the only system I managed to brick(almost). I put a bad config in(never disable usb on a laptop where everything is usb) and there was no easy way to reset it. I had to buy a sioc clip and a chip programmer to reflash the thing the hard way.

The point is all cars have a wonderful battery backup system, and resetting the computer when power is lost is also a nice feature.

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

#368

Post by egeozcan »

o10449366 wrote: post #324
adversaryIdiot wrote: post #254

Earlier quoted context omitted.

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.

People always think that they are compatible if they share more or less a common understanding in big subjects, but stuff like these really test you.

One of my exes hated onion, and when I look back, this made my life way more insufferable than having to hear the (to me) weird political opinions. "Oh I'd like to have this salad but please no onion, and please don't use a knife that's used to cut onion when preparing!". "I think I smell onion, apparently they ignored the knife comment, can you tell them to pack this and maybe you can eat it back home and I'll just go to the [insert food stall name], so meet in 15 mins there?". Ugh.

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

#369

Post by rjzzleep »

matheusmoreira wrote: post #364
o10449366 wrote: post #324

Earlier quoted context omitted.

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.

I've met a lot of women who do stuff like this... I asked one why and she told me it's because they don't want to be a bother. Fully closing the door makes noise, screwing on lids can make it hard for people to open them later. So they don't. They close it just enough and leave the object in that almost there state.

I think this is more an anecdote than anything else. My wife leaves all sorts of stuff open, and it's really because she's not paying attention, i.e. most of the time she's not fully present.

I'm glad to have read this, it gives me a little comfort to see that other people deal with same issues. Sometimes I just close the door for her when she's in the restroom.

I feel like a lot of these habits come from having lived alone for a while after leaving home. I have a lot of habits that I'm 100% certain I didn't do growing up because my mom would tell me not to. I would probably have kept them if I had started living with other people later. My mom on the other hand now does the things she used to tell me not to and I can't help but think that it is related to not caring anymore after living in solitude for decades.

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

#370

Post by sly010 »

dTal wrote: post #310
Dalewyn wrote: post #294

Earlier quoted context omitted.

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.

At a guess it has something to do with needing to withstand 70+ mph winds. There needs to be considerable force holding the door against its seals at all times, and in a mechanical latching system this force must come from a spring, which must be charged with energy via a good slam. However there are minivans with electronically operated sliding doors, which either power the latch allowing you to gently close the doo…

> I surmise the reason we see it moreso on minivans is because 1) it is particularly difficult to work up enough energy to properly latch a sliding door, due to losses from the 90-degree change in direction at the end, and 2) violently slamming the sliding doors on a minivan is very dangerous to children's fingers.

There is also a third, dumber reason, at least for cargo van slide-doors. The surface area of sliding doors are large. When the door takes that 90 degree turn and moves very fast towards the vehicle, it is pushing a lot of air into the vehicle. The air in the vehicle has nowhere to go, so it acts as an air-spring, slowing down the door. To properly latch the door, you have to really slam it hard. If the windows are down or an other door is open, the sliding doors latches very easily. I thought I was going crazy when my door was closing easily ... sometimes. Some cargo vans even have vents that allow air to escape, but people tend to cover them because they don't know what it's for. But electric sliding doors also solve this problem, by moving slowly and letting the air escape.

TLDR: if you car door doesn't close, open the window :)

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