Troubleshooting 4 Flat Install On a 2012 Jeep Liberty
Question:
Four pin flat wiring I have running lights and left and right turn signal but no brake lights
asked by: David
Helpful Expert Reply:
I am happy to look into it. My guess would be that since all you did was hardwire in a connector and did not install a converter, this is why the lights are not functioning correctly. Because most trailers run on a two-wire system - wherein the brake and turn signals are carried on one wire - the separate brake and turn signals from your vehicle's three-wire system need to be combined so they are compatible with the wiring system of the trailer. A converter combines the brake and turn signal functions of your automobile so that they run on one wire to properly activate your trailer's tail lights. That is why our wiring harnesses like the # 118554 are all equipped with a powered converter. Installing an approved powered converter wiring harness will resolve the issue.
My first question would be, is the 7 way plug in your picture active? If so, there is a much easier way to hook up a 4 flat. You can simply use an adapter like the # PK12716.
Secondly, if this is on a 2012 jeep liberty, we have wiring options that will work for you. If you need to replace a factory 7 way you can use the # 74682. We could also replace all of the factory wiring using the # 118554 and # ETBC7 wiring kits.
My recommendation is to do away with the DIY wiring in your picture and install the # 118554. I have linked our install video below.
(click to enlarge)
Products Referenced in This Question
T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- Powered Converter
- Custom Fit
- 4 Flat
- Tekonsha
more information >
Reese Multi-Plug Wiring Harness for Factory Tow Package - 7-Way and 4-Way Flat Trailer Connectors
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- No Converter
- Custom Fit
- 4 Flat
- 7 Round - Blade
- Reese
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 >
Pollak 7 Pole to 4 Way Connector Adapter
- Trailer Wiring
- Wiring Adapters
- Single-Function Adapter
- 7 Round - Blade
- Plug Only
- 4 Flat
- Pollak
more information >
Product Page this Question was Asked From
20 Ft 4-Way Trailer Wiring Harness - Wishbone Style - 30" Ground
- Trailer Wiring
- Trailer Connectors
- Trailer End Connector
- 11 - 20 Feet Long
- Plug and Lead
- 4 Flat
- Optronics
more information >
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