Chevrolet Repair Questions? Ask a Mechanic for Answers ASAP
HI there, I am Cam. Can I get your first name?At the rear plug, have you checked with a test light clipped to ground if you are getting power back there? I suspect honestly that you are, and the your issue is a ground issue. What I suggest is you splice in a new ground from each circuit board plug black wire to the chassis making sure you bare the metal. I suspect that will correct your issue.
Sorry Hal, had a computer glitch. Its back feeding through other circuits. Try the ground and see.