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BillionPa
12-11-2006, 07:41 PM
i just got a new multimeter after frying my smaller one, seems its drawing 2.6A off the battery when the car is off and not doing anything.

before i start ripping the thing apart, what would even be capable of doing that?

///M-Power 3\\\
12-11-2006, 08:16 PM
i just got a new multimeter after frying my smaller one, seems its drawing 2.6A off the battery when the car is off and not doing anything.

before i start ripping the thing apart, what would even be capable of doing that?

I had a ****ed up general module causing a similar drain on my '89 525i, actually i had the car at the shop and the guy didn't want to pay dealer prices for the GM (it also needed a water pump) so he asked me if i wanted it and gave it to me, lasted another 6 or 7 months till it overheated and the head cracked in 3 places

The freakiest drain problem i ever had was a '88 735i with 38k miles. One night i was moving it into the garage and shut it off. At that moment my phone rang and i sat there for about 10 minutes. All the sudden the display on the cluster lit dimly and the gauges started bouncing up and down.

When does the drain begin? Is it directly after you shut off the car or does it take a minute? Also i am assuming it is a steady drain until the battery dies?

jgardia
12-11-2006, 08:17 PM
Connect the multimeter and start removing the fuses. You'll see at some point that the current went down, and you'll know which circuit is the faulty one.

Good luck,

Jose



i just got a new multimeter after frying my smaller one, seems its drawing 2.6A off the battery when the car is off and not doing anything.

before i start ripping the thing apart, what would even be capable of doing that?

BillionPa
12-11-2006, 08:51 PM
i put the car on the tricke charger because it was cold out, even though the batt was at charge. then 2 days later, batt is at 0.

i removed the ground wire and charged the battery over the last 24 hours, then put the ammeter inline to common ground. spiked at 3.something, settled at 2.6A

so the car was completely off for a day, then instant 2.6A draw. im gonna start removing everything one at a time, although the batt voltage drops .1V every 10s, so i will have to figure it out quick!

BillionPa
12-12-2006, 01:58 AM
fused relay....

in other news... i measured the current draw after fixing the problem as well:

Car with all modules pulled: 20mA
Car with all modules put back in except GM: 20mA
After insertion of GM: 170mA
After letting the car sit for a while in that state: 60mA

genphreak
12-12-2006, 01:27 PM
fused relay....

in other news... i measured the current draw after fixing the problem as well:

Car with all modules pulled: 20mA
Car with all modules put back in except GM: 20mA
After insertion of GM: 170mA
After letting the car sit for a while in that state: 60mA Possible causes;

Amplifiers and other devices that have a direct connection to permanent power as well as an accessory feed (carphone, radio, etc.)

Possibly the glove box torch - esp. if it has old batteries (though I expect only charges when the car is operating)

Old Instrument Cluster capacitors /(on e28 there are NiCad batteries)

Door switch circuit, GM and LKM... main relay, OBC...

If you sink 60mA at rest its worth having a big (120mA) solar panel to keep the battery topped up.

:) Nick

BillionPa
12-13-2006, 12:52 AM
what i mean is, a fused relay was causing the 2600mA current draw.

its all good now, just posting the "good" current figures for future reference.