How does the lighting work on a trailer?

With a trailer connected and the ignition off, the Trailer Lighting Control Module will periodically pulse the lighting circuits of the trailer to verify it is still connected. Depending on the configuration of the trailer lights, the trailer lights may periodically flash as part of the trailer theft deterrent function.

How many lights do you need for a trailer?

For most trailers, turn signal lights, and brake lights are used together, so you would have four wires, for ground, running and park light, then the other two would be for brake and turning signal.

Why are there flashing lights on my trailer?

These flashes may be more visible in dark ambient light environments and correspond to when the Trailer Lighting Control Module pulses the lighting circuits to ensure the trailer is still connected. The flashing or flickering lights is a normal condition.

Can a trailer be disconnected with no lights?

If a trailer is disconnected while no trailer lights are active, the trailer will continue to be reported as connected by the trailering app. Always have the vehicle lights on when disconnecting the trailer to ensure the system properly detects the disconnection.

What to do if your trailer turn signal is not correct?

If you still have the problem, disconnect the trailer to test the 4-Way on the vehicle using a circuit tester like # 40376. First, test the wiring going into the convert box on # 118426 from the vehicle tail light wiring. If the signals are not correct then you have a problem with the vehicle wiring.

Why do my trailer lights blink at the same time?

If you find that the signals are incorrect coming out of the converter then the converter has gone bad and it will need to be replaced. If the signals are correct coming out of the converter to the 4-Way then the issue is on the trailer side wiring. You will need to check the grounds at the trailer connector and the trailer lights.

For most trailers, turn signal lights, and brake lights are used together, so you would have four wires, for ground, running and park light, then the other two would be for brake and turning signal.

What should I do if my trailer lights are not working?

Test all of the lights, from the backup lights to the turn signals and brake lights to ensure the problem is not the tow vehicle itself. If the vehicle’s lighting system functions as designed, grab a trailer wiring tester to check the tow vehicle socket. However, the tester must fit the tow vehicle socket.