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Old 01-22-2011, 03:40 PM
G. P. Burdell's Avatar
G. P. Burdell G. P. Burdell is offline
Rambling Wreck
Location: Southeastern U.S.
Join Date: Jan 2006
Posts: 2,072
Mein Auto: E46
Originally Posted by bluebee View Post
The current tribal knowledge assumption is that the wiring loom is a tad too short, hence the stretching pulls the insulation apart at a certain point, and eventually breaks the wires.
I'm going to have to respectfully disagree with the "tribe" on this one. Based on my experience with my previous E36 and now my E46, the problem is not that the wire harness is too short. The problem is the way in which the harness is designed to fold and unfold every time the trunk is opened and closed. All of that repeated flexing and exposure to heat and cold will cause the PVC wire insulation to crack and the strands of copper wire to break. Tension on the harness has nothing to do with it.

Lengthening the harness will just relocate the stress point to somewhere else along the harness. Too much additional length could also pinch the harness and increase the potential for damage. I believe the best solution is to splice in new wire with a more durable insulation - without adding length - and to check the bundle for damage every few years.

Originally Posted by bluebee View Post
What did you end up doing?
I've been studying my Automotive Electrical Handbook while waiting for the last of the materials to arrive.

Last edited by G. P. Burdell; 01-22-2011 at 04:55 PM.
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