Troubleshooting Trailer Lights Not Working and No Power at the 7-Way on a 2000 GMC Yukon
Updated 10/18/2010 | Published 10/17/2010
Products Featured in This Question
Question:
I am not getting any voltage on my factory 7 prong plug. My Stop and turn signals have not worked for some time now my running lights stopped working. I put a volt meter on and not getting any reading. My lights work on the Yukon. Any suggestions on how fix it?
asked by: David T
Expert Reply:
There could be a couple of causes leading to the lighting malfunction you are experiencing. The first things I would check are the ground connections on the vehicle side 7-Way, trailer side connector, and the grounds for the lights on the trailer. On most trailers, the lights ground through the mounting studs. Make sure that at each ground location, there is no dirt or corrosion. A bad ground connection is one of the leading causes of lighting malfunctions.
You can also probe the wires using a circuit tester # PTW2993 further back behind the plug on the vehicle side to see if the plug itself is the problem. If it needs to be replaced, we have the Replacement Multi-Tow 7-Way and 4-Way Trailer Connectors, # 30955, which is designed to fit your 2000 GMC Yukon (use this part if your Yukon has a round plug and cap instead of a bundle of wires above the spare tire. For a bundle of wires, use # PK11898). You may also need to make a few connections under the hood or check for some blown fuses. I have included a link to an FAQ article that should help.
If the 7-Way on the trailer is old, it may need to be replaced with a new 7-Way. Over time, the internal connections can corrode or pull away causing a bad or no connection. I have included a video below showing the replacement of a 7-Way using a Pollack Black Plastic, 7-Pole, RV-Style Trailer Connector - Trailer End, # PK12706, that should help.
Featured Help Information
Miscellaneous Media
Continue Researching
- Article: Brake Controller 7- and 4-Way Installation Kit (ETBC7)
- Article: Trailer Wiring Diagrams
- Article: Wiring Trailer Lights with a 7-Way Plug (It's Easier Than You Think)
- Q&A: What is the Difference Between a 4-Way and 7-Way Trailer Connector
- Article: How to Choose the Right Trailer Hitch Class
- Article: Brake Controller Installation: Starting from Scratch
- Q&A: What is the Difference Between a Class II and a Class III Hitch?
- Q&A: My Vehicle has a 4-Pin Trailer Plug, but Trailer has 7-Pin Trailer Plug
- Article: How to Measure for Trailer Hitch Drop
- Q&A: 2025 Kia Sportage PHEV
- Article: Wiring Trailer Lights with a 4-Way Plug (It's Easier Than You Think)
- Q&A: Availability of Victron DC/DC Battery Charger With Lithium Compatibility and Engine On Detection
- Q&A: How to Add a 7-Way Connector to a 2015 Ford Transit T250
- Q&A: Parts Needed to Add 7-Way and 4-Way to 2023 Ford F-150