Pass rear turn signal doesn't work

Has any had this problem? Front does work, No power to TS, good ground, tried another harness on that side to no effect (about a foot long in back of taillight). Where can I get a good engine and chassis wiring diagram? 89 chero 4.0 auto

factory service manual
Haynes
Chilton
Haynes and Chiltons have never been a favorite, but they generally have decent wiring schems in them.
If you have a towing harness I would look there first. I had some issues with the tailights on my MJ, and I had some issues where the towing connector was spliced in.

Unplugged harness at steering column plugged back in, now it's working.