The pots might be touching the sides of the control cavity..Happened to me before with an old bass with the cavity shielded...not sure if thats the issue for you though.
You are correct. I wrapped some electrical tape around the sides of the pots, and the problem went away.
I think that might vary. My wiring/solder joints appeared robust when I had it open. Rosin spatters told me mine was hand soldered. I think mine was an early run. If all the harnesses are hand soldered, there could be a wide range of fragile to robust harnesses out there. View attachment 4067257
That being said, I think the most likely cause of @G19Tony's issue is, indeed, a short circuit. Since the pickup is responsive when the pickguard is loose, it's not a broken joint. Something is causing a ground short when it's tightened, most likely a bare portion of a "hot" lead to the shielding ground.
It's a P Bass circuit. There's not many culprits to examine.
It was a problem with the pots touching the sides of the shielded cavity. I put in a new, prewired harness from 920D Customs. 920D Custom I bought full size pots, and I believe that to be the issue. I wrapped electrical tape around the pots, and the issue went away.
I'll run this until I start having issues, then I'll get mini pots, and rewire the whole thing myself.


