Battery drain - .13 amps with all fuses removed?

[JGood]

If 60ma is not too much... and my battery is good (put in a known good one from my other e30), alternator is less then a year old... what else could be wrong? I can drive the car all day, park it, start it an hour later, everything is great. It's when I leave it sit 24+ hours that it dies - and it is completely dead when it dies, not a single bit of power to anything. Then I jump it and its fine until I leave it sit again.

The car is in excellent shape, no shady wiring jobs or hacked up components.

[AndrewBird]

Check the voltage at the battery with the car running. Should be ~14V. If it's lower, then your alternator is bad.

A bad battery will kill an alternator pretty quick since it makes it work harder to charge it back up from dead. If a battery dies completely, you should ALWAYS pull it out and use a charger to recharge it.

[JGood]

Check the voltage at the battery with the car running. Should be ~14V. If it's lower, then your alternator is bad.

A bad battery will kill an alternator pretty quick since it makes it work harder to charge it back up from dead. If a battery dies completely, you should ALWAYS pull it out and use a charger to recharge it.

It's ~13.9 Like I said, I can drive it all day, park it, and start it an hour later no problem. The alternator was recently replaced as well.

[StereoInstaller1]

So what happens when it sits overnight? Have you tested battery voltage after sitting? Battery might be bad after all. Are you familiar with "skin (or surface) charge"? That is when the battery test as good voltage, but not enough amps to do the job.

Go find somwhere that has a conductivity meter...a battery tester that measures the CCA of your battery, using a digital meter (NOT a damn load tester, useless crap) made for the job.

If your draw is only 60mA, I bet your battery is shit.

Luke

[JGood]

So what happens when it sits overnight? Have you tested battery voltage after sitting? Battery might be bad after all. Are you familiar with "skin (or surface) charge"? That is when the battery test as good voltage, but not enough amps to do the job.

Go find somwhere that has a conductivity meter...a battery tester that measures the CCA of your battery, using a digital meter (NOT a damn load tester, useless crap) made for the job.

If your draw is only 60mA, I bet your battery is shit.

Luke

Well, I put the car back together yesterday, and left it sit until today. 24 hours. Started fine. I drove it to work tonight, so I'll see if it's dead when I go to leave! If not, I'm sure the problem will come back at the worst possible time...

[xLibelle]

i have found a simular drain in my electrical system, but havent pinpointed it.
your drain, if like mine, will be fine as long as you drive the car on a pretty regular basis. i let mine sit for the week while working and drive on the weekend, come to find it a month later, dead. charge it up full, great, fine, but after a while, its dead again.
And a small trickle like .07 amps will do it too. it wont be a bulb, but something smaller.

if you find it jgood, please share

[JGood]

60 miliamps on fuse 21 won't drain the battery in 24 hours, apparently.

Left my car sit 24 hours, had 12.6 volts. Drove to work, parked for 8 hours, cranked right up afterwards.

On my way home, however (first time driving long distance since problem started), the cruise control kept shutting off. Looked in the rear view, when the cruise wasn't working, the brake lights were on. Brake light switch is borderline out-of-adjustment.

I bet it was coming on while the car was parked in my garage and killing the battery.

[DaveSmed]

Guessing this is the '85? Even though its likely only out of adjustment, there is a recall for the brake lights sticking on due to burnt contacts in the brake switch. (BMW forgot to add the current draw for the USDM third brake light. oops.)

I'd see if you can have a dealer check your VIN, who knows, might get lucky and get a new adjusted free switch without having to even crawl under the dash.

Thats it for the good news. Bad news is your theory is wrong, as the brake lights are only powered with the key on. Back to the drawing board.

[JGood]

Guessing this is the '85? Even though its likely only out of adjustment, there is a recall for the brake lights sticking on due to burnt contacts in the brake switch. (BMW forgot to add the current draw for the USDM third brake light. oops.)

I'd see if you can have a dealer check your VIN, who knows, might get lucky and get a new adjusted free switch without having to even crawl under the dash.

Thats it for the good news. Bad news is your theory is wrong, as the brake lights are only powered with the key on. Back to the drawing board.

Yeah this is the 85 eta. The switch is out of adjustment, I've been having problems with it. I did a five speed swap, and had to piece together the bracket parts and I'm pretty sure something isn't right, but I bent the bracket to get it where it should be. I'll just need to adjust it a bit more.

That sucks about the brake lights not working unless they key is on. Well, I'll see if it starts today... but as of yesterday the problem disappeared...