85 Gmc Wiring Diagram. The other trigger wire has to be connected to the ac compressor clutch relay wire. 85 connect to the power source that you want controlling the switch.
But on a 99 02 the pcm only has pin 42 available to use. Here is a wiring diagram of how the fans are factory wired on the 05 06 gm trucks. Heres one to watch.
Interior and engine wiring harness connector engine compartment fuse and relay box valid for engine 113.
Gmc engine fault codes dtc. Learn to read and then use the applicable wiring diagrams. Replies 0 views 140. Research 1989 gmc sierra 3500 specs for the trims available.