Overview
Driving at night without trailer lights isn’t just inconvenient—it’s dangerous and illegal. Recently, a professional driver called Rocky Mountain Truck Centers when they discovered their trailer lights had gone completely dark just before a long haul.
Customer Concern
The driver reported that none of the trailer lights were working, including running lights, brake lights, and turn signals. They pulled over safely and contacted RMTC for immediate roadside support.
Breakdown Location
The unit was parked safely on the shoulder near a busy highway, where visibility was low and traffic volume was high, adding urgency to the repair.
Diagnosis
Upon arrival, our technician:
- Performed a quick visual inspection of the trailer light plug and wiring harness.
- Tested voltage at the tractor’s trailer light receptacle.
- Confirmed no power was reaching the trailer light plug from the truck.
Further inspection revealed a fault in the wiring circuit feeding the trailer connector.
Repair Story
To resolve the issue and get the unit safely back in service, our tech:
- Isolated the affected circuit using a multimeter and test light.
- Inspected the wiring from the fuse panel to the trailer plug.
- Located a damaged section of wiring that had chafed through insulation and lost continuity.
- Repaired the damaged wiring with proper connectors, heat shrink, and loom protection.
- Verified the correct fuses and relays were in place and functioning.
- Performed a full lighting check (running, brake, turn, and hazard lights).
Result for the Customer
The driver avoided a potential citation, improved safety in low-light conditions, and minimized downtime thanks to RMTC’s prompt roadside response.
Before
Trailer completely dark with no active lights on the rear of the unit.
After
All trailer lights restored and verified in a full walk-around inspection.
