Gentlemen,
Today I had cause to investigate a wiper motor electrical fault someone reported on a 2009 Beemer 7 series. Upon disconnecting the power feed to the motor, inspecting the plug wiring showed 3 wires in total. Two of these appeared good for probably 10A or so, the third, thinner wire perhaps 1A tops. The wipers are normally functioning in three options: fast, slow and intermittent. Since the motor was not in an easy location to view fully, I am unable to determine if its case was earthed or not. What is the most commonly encountered scheme for powering up motors with
3 wires, please? I mean, I know how *I* would go about it, but the Bosch, for some reason, have done it differently and I can't work out how without removing it entirely and stripping it. Can some kind soul save me the bother?