How to Determine the Tow Package Wire Functions on a 1997 GMC Topkick 6500

Question:

Hi my 97 gmc 6500 topkick trailer connector wires got all messed up. i was wondering what each wire color is so i can reconnect a trailer without any problems

asked by: Mike

Expert Reply:

To determine the wire functions for your 1997 GMC Topkick you will need to test the wires with a circuit tester such as # PTW2993. The reason for this is that there is no standard for wire color/function and even the manufacturer can change the color of a wire if they run out of the regular color they use.

All you will need to do is have someone sit in the truck cab and go through the various functions, turn signals, brakes, and so on, while you test the wires with the circuit tester. That is the definitive way to determine wire function.

expert reply by: Michael H