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Old 12-04-2012, 03:46 PM
Dandy dog Dandy dog is offline
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Location: Denver
Join Date: Nov 2012
Posts: 18
Mein Auto: 88 325ic
Finally getting somewhere . . .

The problems with the windows and the detector come from the same place: There's a green wire under the driver's side of the dash that used to be hot, but isn't any more.
The wire that's supposed to provide current to both the windows and the detector comes out of a connector that I believe to be C208 (I haven't been able to confirm this because I can't find C208 on any of the wiring diagrams hh sent me. (it's in the "Connector Locations" pictures and in the "Component List" section, but I haven't been able to locate it on any of the diagrams.)
The connector in question has two wires, both green and probably .5 or 1, on one side, and two on the other, one green and one green and red. The latter green wire used to be hot when the ignition is On, but now shows no voltage; the red and green wire, however, is switched Hot.
It's possible that these wires are associated in some way with the Power Window Circuit Breaker that appears on the wiring diagrams (but not on my car: there's a factory filler piece on the dash where the breaker should be.)
Does this speak to anyone? Has anybody ever seen C208 on a wiring diagram?
In a related development, I found that the voltage at terminal 87 of the main relay is only 2.25 volts with the ignition On. This does NOT seem right, and probably accounts for the fact that the IAS isn't buzzing. (Tapping the center terminal of the IAS to 30 or 86 of the main relay should confirm that the IAS is working, right?)
So: I haven't found the source of the problem, but I think I'm narrowing things down.
Any ideas, suggestions or comments?
Thanks again, guys -
(Edit) Wait a minute: That was a reading of 2.25 volts at terminal 87 of the main relay SOCKET, with the relay itself removed. 87 should get its voltage from the other side of the relay; there shouldn't be any reading at all without the relay in place.

Last edited by Dandy dog; 12-04-2012 at 09:56 PM.
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