This is the original wiring diagram printed by GM for dealer mechanics. You can follow the wiring in your truck from bumper-to-bumper. It will help you to understand connector configurations, and locate & identify circuits, relays, and grounds. Although the schematic is in black and white, the color of each wire is noted. You will not find this diagram in your shop manual. The schematic measures 8.5" x 11" when folded up, and opens up to 11" by 38". The diagram pictured is an example of this type when folded, but is not the actual diagram for your vehicle. Buy now for the best electrical repair info - the factory wiring diagram.
Wiring Diagrams Medium/Heavy Truck 1985 GM P4T P6T
This item is original.
11.00 x 8.50 x 0.10 inches
Covers forward control chassis models P4 and P6 with both gasoline and diesel engines. These are forward control chassis typically used for stepvans and buses. See my other items for the separate P6 motorhome chassis wiring diagram.
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