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dece_dece
08-31-2011, 08:31 AM
HI.

I have an electrical short some where.

Does anyone have experience with electrical shorts on there 7 series...


Reason i say there is a short is because the battery keeps on dieing on me!


I had the ecu replaced not to long ago. Maybe it wasnt programmed properly.?

740-iLL
08-31-2011, 01:57 PM
Have you checked your fuse box to see if any fuses are blown?

Have you unlocked your OBC so you can monitor your battery voltage?

Has the battery ever been replaced?

Has the alternator been load tested?

InfiniteDice
08-31-2011, 03:01 PM
You can hook a volt meter between the + battery cable and the + terminal on the battery. With the car off and have someone watch the draw, then pull one fuse at a time until the draw is gone. This will narrow your search to one of the systems on that fuse.

Essentially you are bridging and monitoring the drain on the battery from the systems in the car. I think I read somewhere that up to a .035 amp draw is alright. Procedures for doing this can be found online.

Good luck.

dece_dece
09-01-2011, 12:14 PM
thanks for the replies.

She is now at the mechanic shop.

I did buy a new battery.

and no i havnt load tested the alternator.


the fuses check out to be good but i have not pulled them out one by one to see if i loose power like that and realize where the power is leaking from.

dece_dece
09-17-2011, 08:40 PM
i had to take out the amp and stereo so i dont loose power anymoer!!!!!

steve.325i
09-17-2011, 11:10 PM
Stereos can be pretty bad for this if they are not wired properly. Especially when there is a seperate amp involved. Amps and HU's (assuming aftermarket) have two power inputs - constant & switched. If these are mixed, the wrong parts can be kept alive and drain the battery. Even if just the amp is wired wrong, it can reverse power the HU for a double wammy.
Also remember (well in my 325 anyway) that there is no switched power to the HU. It's live all the time.

740-iLL
09-18-2011, 11:53 PM
Well how old is your battery? If a sound system is pulling enough juice to drain the battery, it could be that the battery is past its prime and should be replaced

Dado 540
09-19-2011, 12:18 AM
also check the trunk lid wires in the plastic casing. The tend to crack there from opening and closing.

dece_dece
09-19-2011, 09:11 AM
I did not mention its aftermarket.
Its stock sound system on the 740il and its still draining.

slemmer
09-19-2011, 09:31 AM
Did you add anything recently that you can remember or is everything stock?

steve.325i
09-20-2011, 01:06 AM
I did not mention its aftermarket.
Its stock sound system on the 740il and its still draining.

Yup, I know ... I just assumed. Sorry.

How about an addition of an iPod interface or SAT?

dece_dece
09-22-2011, 01:11 PM
NO, nothing aftermarket.