is it some type of capacitor? i have the chance to buy a rather inexpensive compressor that matches the bmw part number, but only has one wire on it (i guess to energise the clutch). i'm wondering if the harness needs to have both wires in the plug connected to something to work. thanks in advance.
oh, forgot to mention...the car is about 250 miles away, otherwise i wouldn't bother you guys with this. thanks.