No Brake Lights After Wiring A 1989 Toyota Pickup and Trailer

Question:

Installed a 4-way on my trailor that I tow with a 1989 Toyota pickup. The right and left signals, tail lights, and flashers all work. No brake lights however. Checked all connections. Any suggestions?

asked by: Bob B

Expert Reply:

It sounds as if you may have wired your 1989 Toyota truck with a 2 wire wiring harness like part # 18002. Toyota vehicles have European wiring, which has the turn signal and brake signal circuit separated. For these vehicles a converter is required to combine the stop and turn signals for towing a trailer.

For the 1989 Toyota Pickup you will need the T-One Wiring Harness, # 118379. This harness plugs inline with the vehicle tail lights and has a converter to allow the vehicle stop lights to function properly on the trailer.

If you have a converter on the pickup and the trailer brake lights are still not functioning, but the turn signals do work, you will need to check the converter to see if it is shorted. If this is the case the converter will need to be replaced and the trailer should be checked to be sure there is not a short causing damage to the converter. I have linked a video showing how to test the converter and wiring also.

expert reply by: Robert G