I disconnected the wires on the alternator B+ stud and temporarily connected them with a bolt. This solved the problem. Took the Marelli 55A alternator with internal regulator apart to check the 6 diodes individually. They were all good at 0.480V so now I'm kinda stuck. I haven't found a lot of info on the Marelli alternator here or on other forums, so if anyone can chime in, please do!
When connecting the green wire for the rotor exciter current, I suddenly measure a path from B+ to B-. It's not there when that wire is not connected. Are there additional diodes somewhere that might be blown or does some sort of short cause this, or is it just normal?
