How to Fix Driver's Side Trailer Red Lamps Not Working

Question:

No trailer is hooked up to wiring harness but drivers side red lamps dont work. The fuse is also blown. My trailer plug is clean and so is the harness.

asked by: Jim B

Expert Reply:

If the fuse is blown then that would be the issue.

If you meant to say the fuse ISN'T blown, and your wiring and connections look good then you'll need to test the light assemblies directly by applying 12V power to the power wire. If all of the lights work correctly with 12V power being applied directly to them then that means your wiring is messed up somewhere and needs to be replaced. You can use the following parts to replace the wiring from your trailer plug back to the assemblies:

- 18-Gauge 2-Wire Bonded Parallel Conductor Wire # SWC97FR (sold per foot)
- Deka Heat Shrink Butt Connectors # DW05744-10

expert reply by: Jon G