Is There Ground Wire of Curt Trailer Wiring Harness that Needs to Run to Frame
Updated 06/12/2026 | Published 06/10/2026
Question:
I just got the 55325 wiring harness for my 2007 Mazda B2300 pickup. Instructions say to ground the white wire to the frame. There is no free white wire with the harness, there’s a green, red, yellow, brown and white, but they all go to the black box. I see no free white wire to attach to frame. Am I missing something?
asked by: Larry G
Expert Reply:
Hey Larry, that's a really good question but it looks like the step about grounding a white wire on the Curt trailer wiring harness part # C55325 was left in the instructions by mistake and is something you can skip. It's a very common step for other trailer wiring harnesses so most likely it was added and noone thought twice about it!
Scott M.
6/12/2026
My unit had the white wire, grounded it and the unit worked fine. Was there a production change? Thanks the unit works great.
Product Page this Question was Asked From
Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- Vehicle End Connector
- Converter
- No Tow Package
- 4 Flat
- Plug and Lead
- Plug-In
- Visible
- CURT
more information >
Featured Help Information
Instructions
Continue Researching
- Shop: Trailer Wiring
- Shop: Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
- Video: Review of CURT Custom Fit Vehicle Wiring - T Connector Vehicle Wiring Harness 4 Pole Flat - C55325
- Shop: Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
- Shop: Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
- Q&A: What Do Each of the Lights on Adapter 7 Pole to 4 Pole with Tester and Cover # 47345 Indicate
- Q&A: All Trailer Lights Work Fine Except Brake Lights Will Not Work
- Q&A: Comparing the Curt Round Hitch 13138 and Curt Square Hitch 13019 for a 1992 Ford Ranger
- Q&A: Bearings and Grease Seal for Terran Axle Idler Hub
- Q&A: Troubleshooting Constant Venting on Air Lift Compressor Manifold Valve
- Q&A: Correct Curt Wiring Kit for Towing a Trailer with a 2024 Ford Explorer
- Q&A: What Wiring Harness Fits The 2026 Toyota Corolla Cross Hybrid S
- Article: Brake Controller Installation: Starting from Scratch
- Article: Brake Controller 7- and 4-Way Installation Kit (ETBC7)
- Article: The 5 Best Trailer Drop Hitches You Can Buy
- Article: How to Correct Noise from Exhaust Rattling Against a Trailer Hitch
- Article: Wiring Trailer Lights with a 7-Way Plug (It's Easier Than You Think)
- Article: Troubleshooting 4 and 5-Way Wiring Installations
- Article: Rooftop Cargo Carriers
Larry G.
6/10/2026
Kinda what I thought Just wanted to make sure.