Why Would Trailer Wiring Blow Trailer Running Light Circuit Fuse
Updated 02/20/2026 | Published 06/11/2024
Question:
2011 shorelander for lund.The trailer lights are blowing a fuse in my truck.The fuse is marked trailer running lights.There is a white wire that appears to go from the trailer to the tongue.this tongue swings awayit appears to be from the brake mechanism in the tongue.This wire has come off.Could this be the problem thats causing the fuse to blow.Noting that the brake light and turn signals are not affected
asked by: Jim
Expert Reply:
Hey Jim, what is happening is that the power wire for the trailer wiring running light circuit is cut or exposed and is shorting out to the trailer frame somewhere (which is grounded) and it's causing the circuit to short to ground and blow that fuse.
Loose wiring is definitely a good place to start but it sounds like that's a reverse lockout solenoid circuit.
Product Page this Question was Asked From
35 Ft 4-Way Trailer Wiring Harness - Wishbone Style - 42" Ground
- Trailer Wiring
- Trailer Connectors
- Trailer End Connector
- 4 Flat
- Plug and Lead
- Optronics
more information >
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Jameson C.
2/17/2026
Hey Jim, did you track down where the short was on your Shorelander trailer wiring? Knowing what fixed the blown fuse could really help others chasing a similar issue.