If you need to keep the 7-Way semi active on the truck, then you would need to make an adapter to get it to work with an RV 7-Way. For that you would need a trailer side 7-Way round, # PK11702, a converter, # RM-732, and a vehicle side 7-Way RV style, # PK12-707E.
A semi-7-Way has separate circuits for the brake lights and each turn signal. And RV style 7-Way has the brake lights combined on the same circuit. So, what you would do is use a circuit tester such as # PTW2993 to determine... view full answer...