Hello. I have a 240 wagon. The rear wiper always worked fine. Recently it started not working sometimes and othertimes it worked. Then it completely quit. I checked the black and gray wires that run to it and found the black had 12V. to ground. I guess that is the hot wire. The gray wire had no continuity to ground. Is that one of the wires that route through the roof hinge and maybe it's broken? Can I route that gray wire straight to ground on the tailgate and get a good result?

Also, I looked at Bentley scematic and the wiper was not where the guide said it would be for that model? WUWT? Thanks, JdL