Troubleshooting Trailer Left Turn Signal Not Working on 2019 Chevy Equinox

Published 06/22/2019

Products Featured in This Question

Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector

(76)

$25.92

Hook Probe Circuit Tester

(70)

$13.94

Question:

Will wiring harness 56375 work on a 2019 Chevy Equinox LT? I had this harness installed but the left turn signal doesn’t work on the trailer. I tried the trailer on two other vehicles so it’s not the trailer. Any ideas?

asked by: Mark C

Expert Reply:

According to Curt the # C56375 wiring harness is a fit for your 2019 Chevy Equinox LT. If it wasn't you probably wouldn't even have a compatible connector to plug it into in the first place.

Since it's just the one function and it's definitely on the vehicle side I'd start by checking the relay you installed. Cavity K3 holds the Left trailer stoplamp/Turn signal lamp relay so make sure it's seated properly. If it seems to be, then switch the relays between cavities K2 and K3 and then test both turn signals again. If the problem switches to the right, then the relay is bad. If the problem stays on the left, then check the fuse is in cavity F18 and make sure it's good.

If the problem isn't with the fuse or relay, then it's in the wiring itself. Unplug the Curt harness at the vehicle connector and inspect the pins on both the harness and Chevy. Straighten any that appear bent. If there's still no resolution you need a circuit tester, like part # PTW2993, to test the wires and connectors. Use the tester on the vehicle's plug and make sure each pin is working. It's a brand-new vehicle so this will likely work. Then test the brown wire on the harness. If you find the issue here, it's because the harness is bad and needs to be replaced.

expert reply by: Charles S