Expert Answers about Hummer H2

• No Trailer Brakes When Stepping On Brake Pedal in 2003 Hummer H2 with P3 Brake Controller
• Your 2003 Hummer H2 has the same setup as the GM SUVs and trucks of the same year. You should be using brake controller harness # 3015-P. Make sure that the position of the red wire in the end of he harness that plugs into your H2 is positioned in the top right corner (with the connector clip facing up) next to the blue wire. If it is not in this location move it there. This is the wire that tells the controller that you are stepping on the brake pedal. If the red wire is in the right...
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• P3 Brake Controller Shows Output Shortage All the Time on 2003 Hummer H2
• If you go to where the brake controller is plugged into your 2003 Hummer H2 you can test the pins on the vehicle side to see which ones have power. This test will tell us if there is a short on the vehicle side or if the controller is the problem. You can use a circuit tester such as # PTW2993 or a meter will work too if you have one. One of the pins should have constant power to power the brake controller. One pin should only have power when you step on the brake pedal. If more than...
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