Back on the night before I picked up my parts truck, my truck decided that it didn't want the left brake or turn signal to work. However, the running light functioned as it should (I wired in stop-turn-tail LEDs over a year ago). After a lot time spent removing split loom and poking wires with a continuity light, I finally traced my problem to under the dash. I suppose you could call it the multi-harness junction. For some reason, I have voltage on the turn signal switch side but it doesn't transfer straight across to the opposite harness (I can't recall the name). At the moment, I have a band-aid fix which was to use a paperclip as a jumper. The left turn and brake light function normally which tells me it can only be within this "junction" piece. The green/red tracer wire in the first picture is from the turn signal switch and is where I'm getting voltage when activating the left turn signal, according to my test light but I found no voltage in the green/yellow tracer wire (second picture) directly opposite of it.



I've never been good with electrical and my eyes typically do this... ...when reading schematics. So, what do you electrical gurus think about this one? Should I just replace this "junction" piece with another? I have this parts truck for a reason but, would this piece be any different from non i/c to i/c wiring?

 

Start by tracing schematics one wire at a time with a highlighter pen. Use several colors. And try to focus only on one circuit at a time, NOT the big picture. I learned this MANY years ago diagnosing Lennox equipment. The Chilton manual for the 91 had schematics...did I give what was left of the manual to you?

 

Jeff, I think the manual was in the cab. I'll have to double check. I would think, as far as the wiring I'm concerned with, that i/c and non i/c would be similar. If my problem is this "junction," couldn't I just replace it and, hopefully, be done with it?

 

Can't hurt to try.

 

Bump. Any thoughts??