Troubleshooting Tail Light Issues On A 2007 Gulf Stream Conquest Travel Trailer

Updated 09/12/2019 | Published 09/11/2019

Products Featured in This Question

Pollak Replacement 7-Pole, RV-Style Trailer Connector Socket - Vehicle End

(745)

$15.54

Hook Probe Circuit Tester

(66)

$14.36

Question:

I have stop lights and turn signals but no tail lights. Lights only light up when brake is pressed or turn signal is on. Can someone help me?

asked by: Allen

Expert Reply:

I would start determining if the problem is on the trailer or the tow vehicle side of the wiring. You will need to use a circuit tester like our part # PTW2993 to test the functions of the trailer wiring harness on your tow vehicle. A video is included to show how this is done. While your testing the running light pin on your tow vehicle make sure the connector is clean and free of corrosion. Do the same for the trailer's connector.

If the problem is on the tow vehicle then most likely it's a fuse, a short somewhere between the wiring and the connector of the tow vehicle, or a bad ground connection. Check any trailer related fuses and the ground connection on your trailer connector. If all check out fine, trace the wires from the connector through the vehicle looking for damaged wires.

If you haven't identified the issue on the tow vehicle side, you will then look at the trailer. Trailer electrical problems are often found in the grounds of the taillight assemblies. Make sure they are connected to a clean metal surface. Also make sure the wiring from the taillight assemblies to the trailer connector is free from cuts or exposed wire that would cause a short. Make sure that the ground wire (usually white) on the trailer connector is securely attached to the trailer frame. If the trailer tongue folds, place the ground connection on the main body of the trailer frame, behind the tongue hinge. Move the ground wire to the trailer frame if it is attached to an aluminum section of the trailer body.

If not a ground issue, then inspect your trailer wiring for any damage or exposed areas. Repair and replace any issue spots identified. You will also want to check the bulbs and light assembly too so if there's any damage, they can be replaced.

I attached an FAQ on troubleshooting 4-way installs for you to check out as well. I also attached a picture that shows a generic diagram for trailer wiring.

expert reply by: Patrick R