Troubleshooting Left Side Trailer Lights Not working on 2014 Chevy Silverado

Updated 06/05/2024 | Published 05/13/2016

Question:

Hi I have a 2014 chevy silverado crew cab and I had the dealer put in a brake controller and the plug for the trailer on the bumper.... the problem I am having is that when I plug the trailer in and test the lights only the right side works like the blinker and the brakes but when I try to you the flashers the ones on the truck work but the trailer doesnt I have to brand new trailers I even took them to the trailer store and they couldnt find anything out but to say the wires where right on the trailer they hooked it to another truck.....the dealer said it could be a bad plug adaptor could that be possible.....

asked by: Albert D

Expert Reply:

Don't worry, I can help you troubleshoot this issue with you.

First thing I would check is the fuses under the hood. # 14 is the trailer stop/turn lamps for the left side. I would also check the # 15, 16, 64, & 1 as these are more of the trailer light functions fuses. I have linked an image of your fuse box to this page for your convenience.

If you continue to have issues, just let me know, I would be more than happy to continue to help you troubleshoot this issue.

expert reply by: Jackie C

click to enlarge

Jonathan

6/4/2024

I am literally experiencing the exact same problem. I visually checked the fuses mentioned and they appear to be in good condition. Without a tester I am going to have to assume that they are good. Which wiring harness under the hood should I consider?

Jon G.

6/4/2024

@Jonathan You might also try swapping the fuses around just to make sure they are in good shape. For a different trailer plug I'll need to know the year/make/model of your truck as those wiring kits can be vehicle specific.

Jonathan

6/4/2024

@JonG, that is a good idea on the fuses and I appreciate that troubleshooting insight. My truck is a 2014 chevy silverado 2500 v8 crew cab and I have never used it before but there is a trailer brake device under my steering column. My trailer plug at the bumper is a stacked plug with the 7 round plug on top and the 4 prong on the bottom. I have the 4 prong on my trailer. Not certain if the 7 round plug works 100% or not. I could swing by the Advance and purchase that one I guess although I have no real need for it at the moment.

Jon G.

6/4/2024

@Jonathan Yeah, if the fuses look good then it's definitely worth getting those pins tested to make sure the signal is actually reaching the end of the plug. It's possible that you could have some damaged wiring somewhere under your truck so checking the fuses and then the plugs gives you what you need to know on both ends.