Unfortunately I didn't get a chance to look at this last night but hopefully tonight.
Pat, thanks for the additional idea, I have a good meter.
Adriatic, I did grease the worm gears while I was in there originally, figured it didn't hurt and they looked dry.
Cleaned both rollers the other day, (and wheels) as well as well as portions of both common and center rail where I could reach. I dont think its this because all my other engines are running ok but did it anyway "for fun". I'll check the roller and truck wires for continuity, maybe as suggested before its a cold or bad solder joint.
Will try the flushing of axle/truck mating surfaces.
No rectifier but I do have a fairly large function generator, hope it doesn't come to that but could unbury it from the shop if all else fails.
lol 6V bug! Mine is 12V but still made in Wolfsburg! Unfortunately the bug is a huge project and not out on the road yet. Have completed all restoration underneath, new firewall, headframe, pans, heater channels etc etc, even had to take the cabin off, that was fun! Now I want to rebuild the engine and need to do body work before putting it back to its original color, orange. They said these were "cheap" cars to fix and maintain, guess that only applies if you don't have to replace everything and try to put it back to original as closely as possible. That being said, I did swap out the braking for a safer 4 wheel disk brake system, after I had already bought complete new drum system..........
Again, thank you for all the help and suggestions, will report back on progress so if someone else runs into the same issue they can hopefully find it using the board search feature, (and yes, I did search before posting my question).
Cheers
Marc