Finding Intermittent Ground Problem in Wiring of Trailer Towed By 1992 Geo Tracker

Question:

Hello! So I purchased your Curt brand trailer wiring converter 56175 for my 1992 Geo Tracker as your website recommended. Ive wired everything as per instructions and using circuit tester to verify wire function etc. I tested the lights after wiring and oddly everything works... but only intermittently. The running lights work 100 of the time. The brake lights and appropriate turn signals only work part of the time. Ive read that this is commonly a grounding problem. So I connected a wire from my trailer wiring harness ground at the tongue and ran it to the back light and ran a wire from that back light to the other back light as a wired ground thus not relying on the metal frame as ground. After this, the same issue of intermittent function remained. I then sanded down inside of the vehicle where that ground was attached and it did not help either. The wires from the converter were attached to the oem blue connector 6 wire wiring harness that came with the vehicle for trailer wiring. The black ground wire from the vehicle was attached to the existing vehicle ground... there was a green wire that went unused. All lights signals function perfectly on the vehicle itself. Thank you in advance for your assistance!

asked by: Jeff H

Expert Reply:

I'm still leaning toward a insufficient ground connection as being the cause of the problem you're describing. To confirm it, you'll need length of wire long enough to reach from your ground connection on the trailer tongue to the negative battery terminal on the vehicle. If connecting the wire to the wire to the negative battery terminal fixes the problem, you've pretty much confirmed a poor ground as being the issue.

I'd also check the spot on the tow vehicle where the # C56175 grounds. Make sure this connection is made to clean, bare metal that isn't corroded.

I've linked you to our trailer connector troubleshooting help article.

expert reply by: Mike L