Making Trailer Wiring Adapter for Semi Truck Towing Trailer with RV Blade Style 7-Way
Question:
Could you tell me how to wire a 7pin flat gooseneck trailer with electric brakes to a kenworth t-370 with a 7 pin round
asked by: Paul
Expert Reply:
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 the functions of the 7-Way on the tow vehicle. Then you would place the red wire from the converter to the appropriate spot on the back of the trailer side 7-Way round for brake lights. Do the same with the green wire for right turn signal and the yellow wire for left turn signal.
You will also need additional wire to attach to the back of the 7-Way round for the other functions needed. For ground and 12-volt power you can use # 10-2-1. For running lights, you can use # 16-1-1, and for electric trailer brakes use # 10-1-1.
On the output side of the converter, you will attach the wires to the back of the vehicle side RV 7-Way. The green wire will attach at the 9 o'clock position, yellow goes to the 3 o'clock position. Ground goes to the 5 o'clock position, 12-volt power goes to 11 o'clock position. Running lights goes to the 1 o'clock position. The center pin is for reverse lights which is uncommon on many trailers. But if needed you will attach some wire to the appropriate pin on the 7-Way round pin and attach it to the center pin on the back of the RV style 7-Way.
Products Referenced in This Question
Deka Jacketed 2 Wire, 10 Gauge, Brake Wire - per Foot
- Wiring
- Wire
- Jacketed Wire
- 2 Wire
- 10 Gauge
- Deka
more information >
Pollak HD, 7-Pole Round Pin Connector w/Cable Guard
- Trailer Wiring
- Trailer Connectors
- Trailer End Connector
- Plug Only
- 7 Round - Round
- Pollak
more information >
Pollak Black Plastic, 7-Pole, RV Blade-Style Trailer Socket - Vehicle End
- Trailer Wiring
- Trailer Connectors
- Vehicle End Connector
- Plug Only
- 7 Round - Blade
- Pollak
more information >
Roadmaster Brite-Lite Wiring Converter
- Tow Bar Wiring
- Splices into Vehicle Wiring
- Tail Light Converter
- Universal
- Roadmaster
more information >
Product Page this Question was Asked From
Hopkins Trailer Connector Adapter - 7-Pole Round Pin to 7-Pole RV
- Trailer Wiring
- Wiring Adapters
- Single-Function Adapter
- 7 Round - Round
- Plug and Lead
- 7 Round - Blade
- Hopkins
more information >
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