Expert Answers about GMC T-Series

• Trailer Brake Lights Do Not Work on Trailer Towed by 2004 GMC T7500
• It sounds like 1 of 2 possible issues. First, if the vehicle has separate turn signal lights from the brake lights then you have a 3-wire system and you would need a converter such as # 119178KIT to take the separate signals and combine them. Then you can run the combined signals to the 7-Way by cutting off the 4-Way of the 119178KIT and attaching the wires to the 7-Way. The other possibility is that if the vehicle has combined brake and turn signal lights, the stop light/CHMSL fuse may...
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