Curt Trailer Wiring Harness for 2004 Volkswagen Golf has No Left Turn Signal at the 4-Way

Question:

Installing this wiring kit into a 04 Golf. I have a 12v light tester. I attached the yellow wire to the left turn signal, verified I have flash at the provided tap connector, and on the yellow wire right before the black box I penetrated the shielding with my tester, but no flashing on the other side of the black boxpenetrating the wire shielding or at the trailer plug. What are my next steps to solve?

asked by: David C

Expert Reply:

The wiring system on the 2004 Volkswagen Golf is a complex system. It should have combined brake, tail, and turn signal functions on one wire. This means the red and brown wires are grounded and the yellow wire attaches to the combined brake, left turn signal, and tail light wire and green connects to the combined brake, right turn signal, and tail light wire.

If this is how you have it set up and there is still no left turn signal on the output side of harness # C56175 then that indicates a problem inside of the converter box and the whole harness will need to be replaced.

expert reply by: Michael H