Stereo & Electronics - Normal drain on battery in milliamps?

How much current does the car draw from the battery when the car in parked and not running? My battery is going dead for some unexplained reason. Thanks.

I believe for most cars that 50 mA is acceptable

how long does the car sit before this happens i see it at work quitea bit a alot of times it could be a battery we have a machine at work that asylze it ..take the batt to a advance auto make shure you take it in the battery tester for the car is not that accurete

Just went through a similar ordeal with my C5.

Once BCM shuts down alot of the systems the amperage draw should drop down to the 20-30 millamp range. It can sometimes take 10-20 minutes for this to take place.

I had to put a ampmeter in circuit to test the draw. I found a few problems.
1) My altenator was drawing over 100 millamps on its own. Got it tested , and the voltage reg was faulty...had it replaced and it corrected that problem.

2) My radio was also drawing excessive milliamps. I pulled the fuse for it, and let the system start up, then replaced the fuse. and then it stopped drawing the excess amperage. Not sure what the cause was here. Guessing that it was an issue with the security system, and pulling the fuse reset it.

3) Found that my window switch on my nitrous system was wire to an unswithed power source, and it constantly draws over 100miliamps. I moved it to a switched power source.

Now my amperage draw is right at 20miliamps when the BCM shuts down all the systems. and it takes about 5 minutes for it to get there.

No more draining batteries!!!!!!

P.S. NEVER EVER USE AN OPTIMA RED TOP!!! ONCE IT GOES DOWN...ITS WORTHLESS MIGHT AS WELL THROW IT AWAY.

Arg! I've got 105 milliamps after it settles down. so obnoxious. Trying to track it down. so far i've tried all the engine compartment fuses. that would rule out my alternator right? btw, how do you pull the fuses in the door w/o having the interior lights drawing power?

Arg! I've got 105 milliamps after it settles down. so obnoxious. Trying to track it down. so far i've tried all the engine compartment fuses. that would rule out my alternator right? btw, how do you pull the fuses in the door w/o having the interior lights drawing power?


Be sure to give it plenty of time to switch off the various systems. Some people on other forums report that it can take up to 20-30 minutes.


Here is how I checked my altenator... I got my meter setup to measure the draw on the battery...gave it 20-30 minutes to get to its base line. Then I disconnected the wire at the back of the altenator, and the little plug that plugs into the altenator. My milliamps dropped significantly as soon as I disconnected the cable at the back of the altenator.

My car is a C5.. I had the relay removed from the floorboard fuse box that turns on the courtesy lights. Not sure on the Fbody...been a while since I had mine. Any way to easliy pull the bulbs, or possibly disconect a plug feeding them.

I would always have to pull a fuse...then shut the doors, and run the test. Mine won't power down some of the sytems with the doors open.

http://forums.corvetteforum.com/showpost.php?p=1555274323&postcount=7

One easy way to keep the bcm from activating after you unhook the ground from your battery is to use a jumper.

Here is a procedure I used.

http://www.ls1tech.com/forums/showthread.php?p=5576007#post5576007

P.S. NEVER EVER USE AN OPTIMA RED TOP!!! ONCE IT GOES DOWN...ITS WORTHLESS MIGHT AS WELL THROW IT AWAY.
Well, hey. At least you get a 3 year free replacement. Yellow top is only one year.

Now my amperage draw is right at 20 milliamps when the BCM shuts down all the systems. and it takes about 5 minutes for it to get there.
Exactly the same for me on my 99 TA.