There is a square connector that goes to the body near the injection pump, it has wires for the temperature sensor for the Glow relay, the HVAC pushbutton and the gauge in the cluster. - should have a white, blue and some else.


I think you are looking at the idle speed control piece, it has a red wire (solid 12V) and a controlled ground from the ELR cube (idle speed) - there is another connector there in the harness that doesnt connect to anything, the difference is that its straight and the idle one in angled.

If you cannot find a wiring pointer for it, trace the wire to the harness big connector and trace it back to one of the controller holders there, the entire thing unbolts and you can then DMM it. The colors are also visible if you pop the back of the connector shells off.

Just remembered, the one extra connector you will have, will only have one wire in it. Leave it be - it doesnt go anywhere.

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)