Troubleshooting Truck Brake Lights That Come on When Truck is Off
Question:
The brake controller occasionally activates my truck brake lights when truck is not in use!
asked by: Ken M
Expert Reply:
Since a trailer brake controller does not actually generate any lighting signals, the cause for your truck brakes lights occasionally coming on is likely to be some corrosion or trapped moisture/dirt on or inside the trailer socket on the truck or the plug on the trailer.
It can happen that corrosion can cause two adjacent circuits to become bridged together. If you refer to the linked photo you will see the typical wiring configuration for a vehicle 7-way. You'll note that the 12V auxiliary power circuit (1-o-clock position) is next to the taillight circuit (11-o-clock position) and a bit of foreign material, water or corrosion could bridge these circuits. Inspect both the vehicle socket and the trailer plug. Corrosion can sometimes develop even inside a connector, which will require replacing it.
You can try unplugging the brake controller from the wiring harness; if the condition still occurs then you know the problem is not in the controller but in the wiring.
Product Page this Question was Asked From
Tekonsha Prodigy P3 Trailer Brake Controller - 1 to 4 Axles - Proportional
- Trailer Brake Controller
- Proportional Controller
- Electric
- Electric over Hydraulic
- Automatic Leveling
- Under-Dash Box
- Dash Mount
- Up to 4 Axles
- LCD Display
- Up to 360 Degrees
- Tekonsha
more information >
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