Trailer Tail Lights Do Not Work/No Power On Brown Wire in Wiring Harness 118438 2005 Honda Odyssey

Question:

05 Honda Odyssey, Lights work fine on tow vehicle. Turn signals, brake lights and hazard lights all work fine on trailer but running lights and tail lights on trailer do not work at all. Im not getting any power to the brown wire on the 4 pole connector on the tow vehicle. Do I need to replace the entire harness?

asked by: Gene J

Expert Reply:

You can test the wiring harness, # 118438, to determine if it is functioning properly. First, use a circuit tester, like # 3808 if needed, to test the wires going into the converter from the vehicle. If there is no signal for the running light circuit then the issue is on the vehicle. If the signals are correct going into the converter but incorrect coming out to the 4-Way then the converter is bad and it will need to be replaced.

If you determine the issue is on the 2005 Honda Odyssey you can use the vehicle owners manual to find the locations of any fuses/relays related to the trailer wiring. Check those to see if they are working correctly or if they need to be replaced.

If you did not install the included fuse in the fuse compartment, step 4 in the instructions linked for reference, then the harness will not work properly.

expert reply by: Michael H