Lionel Milwaukee Road BiPolar intermittent short

I have a Bi-Polar that stalls on switches.  There is no continuity between the front and rear pickup rollers so a wire has parted inside, but not shorting so far.  It's waiting for some TLC.

Not sure if you have a wiring problem or a circuit board problem.  See this thread that discussion burnt board trace on earlier Bipolars.

https://ogrforum.com/topic/lio...ter-pcb-design-fault

@Steims thanks for the post that I will read. So far, I have convinced myself that wire(s) have had insulation compromised by rubbing against a drive wheel as body sways through my 072 Ross switch, and can occasionally short out.

I have to get some time and courage to try and remove the shell and try to get a better look.

My original post was to try and find out if the wiring between the body sections of the Bi-Polar were wired just above the trucks as I tried to show in the pics, or were the wires supposed to have been run from body section to body section directly within the body section shells. If you look in particular at my last pic, you can see the wires are right at a drive wheel.

Not sure what the issue is, but I wouldn't run it until you chase it down.  Stuff like that has a propensity to take out the boards!

I did have the shell off of a MR EP-1 a few years ago and I don't recall much difficulty.  Just the 4 screws per shell.  I recall the need to use care not to allow either cab to rub the center section especially since it articulates.  It will scratch/rub paint off.