red lights on 7way circuit chaser

[green_380]

'84 R model showing all red lights except aux when circuit chaser is plugged in. Any idea what could be causing red lights. When a circuit is chosen it turns to green except turn signals that when activated green and red light fluctuates on blinker. Thank you in advance.

[Joey Mack]

A ground fault. Clip a wire to the ground pin and the truck and see if it changes. 

[revnexis]

On an ’84 R-Model this is almost always a ground issue or voltage back-feeding. All red lights with the circuit chaser usually indicate a poor cab, frame, or rear light ground, often from corrosion. The turn signal flashing red and green is a classic weak ground at the rear lamp housings or a bad cab-to-frame ground strap. I’d start by checking and cleaning the cab-to-frame ground, battery/frame grounds, and rear light grounds before chasing switches or wiring.