Troubleshooting Trailer Lighting Errors on 2017 Ford F-350 and Trailer Light Functions
Question:
Getting fault codes trailer light module fault , right signal fault , replaced one of the two as the lens on one was cracked , led light works but no signal on either , I’m assuming it’s a short somewhere but could also be the truck , any ideas where to check first , had the signal fault before but the light / brake and signal still worked , now nothing but a tail lamp
asked by: Kevin G
Expert Reply:
LED Lights draw much less power than an incandescent light, so you may need to add a load-resistor to get the draw for your lights to work and sensor to go off. The 7-Way to 5-Way/4-Way Trailer Adapter for Vehicles with Lamp-Out Sensors Towing Trailers with LEDs # C35FR and the 7-way # 20142 both have integrated load-resistors.
Because your lights worked before, I recommend checking your ground connections to make sure they are free of rust and corrosion and have a bare metal to metal connection. Once you know your ground connection is good, then you can troubleshoot the wiring if needed with a circuit tester like # PTW2993. You can probe through the insulation on the wires to determine if you are getting power or not and that will let you know if you have a short and a wire that needs replaced.
I've attached a couple wiring article to help.
Products Referenced in This Question
Trailer Connector Adapter w/ Lamp-Out Sensor Bypass - 7-Way RV to 7-Way RV - Vehicle End
- Trailer Wiring
- Wiring Adapters
- Single-Function Adapter
- 7 Round - Blade
- Plug Only
- 7 Round - Blade
- Tow Ready
more information >
Product Page this Question was Asked From
7-Way to 4-Way/5-Way Trailer Adapter for Vehicles with Lamp-Out Sensors Towing Trailers with LEDs
- Trailer Wiring
- Wiring Adapters
- Multi-Function Adapter
- 7 Round - Blade
- Plug Only
- 5 Flat
- 4 Flat
- CURT
more information >
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