I Have Working Running Lights, but No Turn Signals or Brake Lights on Trailer

Question:

I have a 2021 Jeep Gladiator and just bought a 2021 Forest River Wolf Pup camper. The plug for the brake/running lights fit but all i get is running lights in Run position, they go off in Auto, No brake lights or signals. What am i missing?

asked by: Greg R

Helpful Expert Reply:

The first thing that you want to do is make sure that your 2021 Jeep Gladiator's turn signal and brake light fuses are operational. Some vehicles with tow packages have fuses for operating the turn signals and brake lights. According to the research I conducted, the fuses that you need to check are F107 and F109.

Another thing to consider is whether the wires on the 4-way connector are plugged in correctly. It is also important to consider that each light is grounded to the trailer frame and that the connection to the trailer frame is free of rust, paint and corrosion. I went ahead and included a helpful FAQ article that shows the wiring route of a 4-way harness.

As a third possibility, there may be corrosion in the connectors themselves and whether there is fraying or pinching at any point along the wires.

expert reply by: Bob C