Why is There Only One Ground Wire on the Adapter 4-Pole to 7-Pole and 4-Pole Part # 37185
Question:
On part #37185 why is there no ground wire coming off of the Four flat connector that plugs into the existing 4 way? Is the single white wire the ground for both the 4 flat and 7 round? If so can i use the part #40105 T connector in my wiring harness to add a 4 way connector for #37185 to connect to? My Truck is a 1978 f150
asked by: Joe
Expert Reply:
The Adapter 4-Pole to 7-Pole and 4-Pole part # 37185 has both 4 and 7-way trailer connectors. There is only one ground wire for both connectors as that is all that is needed. The ground wire for the 7-way and 4-way trailer connectors are combined into one wire which eliminates the need to ground two separate wires with the same function. If you will be towing a trailer with brakes you will need the wires that connect the 7-way connector to a brake controller and for that you will want to use the Universal Installation Kit for Trailer Brake Controller part # ETBC7 instead.
Either of the above adapters can absolutely be used in conjunction with the Hopkins Plug-In Simple Vehicle Wiring Harness part # 40105 on your 1978 Ford F-150. If you also need a brake controller, the Tekonsha Voyager Trailer Brake Controller part # 39510 with the Brake Control Plug-In Harness for Tekonsha Brake Controllers part # 20127 is an excellent option and will work well for you.
I have attached a review video of the wiring harness, brake controller, and both adapters for you as well.
Products Referenced in This Question
Replacement Brake Control Plug-In Harness for Tekonsha and Draw-Tite Brake Controller 12" Long
- Accessories and Parts
- Trailer Brake Controller
- Wiring Adapter
- Plugs into Brake Controller
- Universal
- Draw-Tite
more information >
Tekonsha Voyager Trailer Brake Controller - 1 to 4 Axles - Proportional
- Trailer Brake Controller
- Proportional Controller
- Electric
- Manual Leveling
- Under-Dash Box
- Dash Mount
- Up to 4 Axles
- Indicator Lights
- Up to 90 Degrees
- Tekonsha
more information >
Hopkins Plug-In Simple Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- No Converter
- Custom Fit
- 4 Flat
- Hopkins
more information >
Universal Installation Kit for Trailer Brake Controller - 7-Way RV and 4-Way Flat - 10 Gauge Wires
- Accessories and Parts
- Trailer Brake Controller
- Installation Kits
- etrailer
more information >
Product Page this Question was Asked From
Adapter 4-Pole to 7-Pole and 4-Pole
- Trailer Wiring
- Wiring Adapters
- Multi-Function Adapter
- 4 Flat
- Plug and Lead
- 4 Flat
- 7 Round - Blade
- Hopkins
more information >
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