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Old 10-15-2012, 04:00 AM
Billwill Billwill is offline
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Location: South Africa
Join Date: Oct 2009
Posts: 529
Mein Auto: BMW E30 318i 1991
The problem with a current drain such as you are having is that often it does not help removing for instance the bulb from the trunk......the problem may be that the leads going to the bulb in the trunk may be partially shorting to ground or shorting to another cable inside the harness...removing the bulb at the end will not change matters much.

You need to be somewhat brutal stated put an Ammeter in series with the battery and note current drawn.
Pull fuse 21 out...current drops significantly.

Now you have to trace where the output of fuse 21 actually goes....according to my circuit diagram it is a Red/Green wire which then branches out to seven other locations...all using Red/Green wires.

These locations are:
Instrument cluster pin A2
Trunk light
Chime module
Auto charge flashlight
Left dome light
Right dome light

You need to find where these wires branch off from the main lead and on by one physically cut them off at the branch with a wire cutter until you find the one causing the problem.

You then re-join the innocent wires and insulate...preferably with shrink-tubing insulation.

The faulty wire you can try to physically trace to see if it is fraying somewhere but if it is inside a thick loom full of other wires it is best to cut that wire off at both ends and lay a new wire to replace it.

I have had to do this procedure about 6 times on a Jeep that I own due to accident damage causing several wires inside a large loom to have partial shorts to ground or partial shorts to other wires lying next to them in the loom.

Last edited by Billwill; 10-15-2012 at 04:02 AM.
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