Installing 4-Pole/7-Way Trailer Connector on Newmar Motorhome
Question:
I recently bought a Newmar motorhome which came with a 7 pin flat plug. I have a car dolly, also with a 7 pin flat plug. I also bought magnetic tow lights to put on the trunk of the towed vehicle. These have a 4 pin plug. How do I attach both. Is there an adapter that retains the 7 pin plug and adds a 4 pin plug, so I can use both?
asked by: Bob
Expert Reply:
There is not an off-the-shelf adapter that would convert your existing 7-way flat blade to a 7-way and 4-pole, but there are some fairly easy options for adding a 4-pole.
You can access the wiring harness leading to the existing 7-way, and tap in a 4-pole harness like part # 18252, which would allow you to use both harnesses simultaneously. The connector includes a circuit tester which would help identify which circuit serves which lighting function.
Another option would be to completely remove your existing 7-way and install a 7-way/4-pole connector like part # HM48470. If you take a look at our wiring FAQ article, you can see how a 7-way is wired. Be sure to wire by function using a circuit tester rather than wire color.
I have linked you to an install video that will help you through the install process. Keep in mind that you will want to use a tester to verify the function of the wires on the RV.
Products Referenced in This Question
4-Way Flat Trailer Connector w/ 72" Harness, Circuit Tester and Wire Taps
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- No Converter
- 6 Feet Long
- Universal Fit
- 4 Flat
- Tekonsha
more information >
Hopkins Endurance Multi-Tow 7-, 5- and 4-Way Flat Trailer Connector - Vehicle End - Ergonomic Design
- Trailer Wiring
- Trailer Connectors
- Vehicle End Connector
- Plug Only
- 4 Flat
- 5 Flat
- 7 Blade
- Hopkins
more information >
Product Page this Question was Asked From
Hopkins Endurance Universal 5th Wheel/Gooseneck 7-Way RV Extension Cord - 8' Long
- Custom Fit Vehicle Wiring
- Fifth Wheel and Gooseneck Wiring
- 8 Feet Long
- Universal Fit
- 7 Round - Blade
- Hopkins
more information >
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