Hello all

Have been looking over an acquaintances coupe. The symptoms pointed to a bad RCM and so I plugged my working one in. Only an occasional crank for a second or two. Radiator fan did not kick in.

I suspected that it could be a bad crankshaft position sensor but common sense told me that there would be a crank at least although one of the videos in this forum suggests that is not always the case…

I understand starter motor failures are really rare and I have heard it crank like I said. What should I check next? The control module in the fuse block? Try bypassing it to fire the starter?

Much appreciated all. Would love to stop this car going to scrap…