Troubleshooting Malfunctioning Marker Lights on Trailer
Updated 05/11/2015 | Published 05/09/2015
Products Featured in This Question
Question:
Why isnt my marker light working
asked by: James W
Expert Reply:
First, check to see if any of the other marker lights are working. If not, check that the running lights are working at the rear of the trailer, as they're all on the same circuit.
If none of the running/marker lights are working, unplug the trailer and check the running light pin on the vehicle's trailer connector while the headlights are switched on, using a circuit tester like part # PTW2993. If you get power on the running light pin, the problem is in the trailer wiring.
If it's just the single marker that isn't working, first check the wiring connections. Make sure the power and ground connections are tight. Some lamps get their ground from a wire connected to the trailer frame, others from the mounting stud being in contact with the trailer frame. Use the circuit tester on the power wire to ensure power's reaching the lamp. Check the bulb to see if its burned out or if the bulb socket is corroded.
If none of the running lamps are working, check the connector on the trailer for damage or excessive corrosion. Trace the running lamp circuit (usually a brown wire) from the connector to the lamps. Look for pinched wires or loose connections.
I'll link you to our trailer wiring troubleshooting FAQ article.
Product Page this Question was Asked From
Peterson Trailer Tail Light Kit - Waterproof - Stop, Turn, Tail - Incandescent - Oval - Red Lens
- Trailer Lights
- Tail Lights
- Brake/Tail/Turn
- Oval
- Recessed Mount
- Submersible Lights
- Incandescent Light
- 6-1/2L x 2-1/4W Inch
- Red
- Peterson
more information >
Featured Help Information
Miscellaneous Media
Continue Researching
- Search Results: trailer lights
- Q&A: Trailer Tail Lights With 2-Prong Connector For ShoreLand'r Boat Trailer
- Shop: ONE LED Trailer Tail Light - 6 Function - Submersible - 6 Diodes - Red Lens - Driver Side
- Shop: LED Combination Tail Light Kit for Trailers under 80" Wide - Submersible - Driver and Passenger
- Shop: Combination LED Trailer Tail Light - Submersible - 6 Function - 11 Diodes - Passenger Side
- Shop: TecNiq Contoured Seven Function Box Style Tail Light - Passenger Side
- Shop: Optronics Combination Trailer Tail Light - Submersible - 7 Function - Incandescent - Passenger Side
- Shop: ONE LED Trailer Tail Light - 5 Function - Submersible - 3 Diodes - Red Lens - Passenger Side
- Shop: LED Tail Light for Trailers Over 80" Wide - 8 Function - Submersible - 23 Diodes - Driver Side
- Shop: Trailer Hitch
- Search Results: trailer hitch
- Q&A: Lug Nut Torque Chart for Trailer Wheels
- Article: Trailer Wiring Diagrams
- Article: Brake Controller 7- and 4-Way Installation Kit (ETBC7)
- Shop: Trailer Wiring
- Q&A: What is the Difference Between a Class II and a Class III Hitch?
- Search Results: trailer tires and wheels
- Shop: Suspension Enhancement
- Video: Measuring To Choose The Right Trailer Axle
- Q&A: What is the Difference Between a 4-Way and 7-Way Trailer Connector
- Search Results: trailer wiring
- Article: Wiring Trailer Lights with a 7-Way Plug (It's Easier Than You Think)
- Article: Trailer Lighting Requirements
- Shop: Brake Controller
- Video: How to Choose a Trailer Brake Controller
- Search Results: trailer jack
- Q&A: Installation Time for Blue Ox BX1128 Flat Tow Base Plate Kit for 2016 Jeep Grand Cherokee
- Q&A: Does etrailer Carry Furrion Chill Cube w/ Heat Pump to Replace Dometic Duo-Therm
- Article: How to Measure for Trailer Hitch Drop
- Shop: Gooseneck Hitch
on Trailer Lights
