On my 84 318i there is what like a switch located in the engine compartment near the battery. It has to leads that come from it. It looks like you can unscrew it from the engine compartment but must be pulled out in the glove box or remove the dash. One of the leads broke off and I think i must replace it, but I don't know what it is. Any help. The wires are green/yellow and looks like blue/yellow. It does looks like a switch of some kind. Maybe goes directly to ecu? Thanks for your help.