Troubleshooting Sparks on Safety Chains When Connecting to Hitch

Updated 11/30/2024 | Published 08/19/2020

Question:

I install the Curt T-Connector Vehicle Wiring Harness for Factory Tow Package - 7-Way Trailer Connector on my 2019 infiniti QX60 per instruction. no issues with the installation. But when I hook up the travel trailer, there are visible sparks between the trailer safety chain hooks and Hitch Receiver. I was told there might be issues with the grounding. Please advise if there are ways I can check what is going on and how to fix the problem. Thanks.

asked by: Alex C

Expert Reply:

What you've been told is likely the culprit, and I don't believe that it's coming from an issue on the Curt # C56357 you've installed. I would check the ground wire on the trailer wiring harness to make sure that it is connected to a paint, rust and debris free spot on the trailer frame. This is the most likely cause of the sparks that you're seeing. If you can check this and see if it continues, that's a good place to start. If you're still experiencing the same issue after cleaning off and re-attching the trailer ground wire, let me know and I can give you a few other things to check out.

expert reply by: Erik B

Dave K.

11/29/2024

Hi. I have a 2017 Mini Cooper S towed by a 2018 Dynamax Isata 4 31 DS. I bought from you and installed a Roadmaster 154-792-118158 wiring kit and a Roadmaster RM-156-25 charge line kit. The lights worked fine when hooked to the 7 to 6 pin cable. When I hooked up the safety cables, they arced and tripped the circuit breaker for the charge line. I double and triple checked everything I can think of and still have the issue. The tow vehicle definitely has a good ground - the RV is the factory wiring to the 7 pin connector. I’m not sure how to check that ground at the connector. The other odd thing is that the towed vehicle lights do not work unless the charge line is connected - I thought they should work regardless. Thanks for any help you can give.

Kevin C.

11/29/2024

@DaveK The lights and charge line are completely separate so one would not affect the other. Connecting the safety cables should not have caused anything to arc and would only if there was bare wiring touching the metal it's connected to. You definitely have something crossed though if your lights require the charge line kit to be working. Can you email me some pictures of your setup so I can get a better idea of how you ran these?

Dave K.

11/30/2024

@KevinC thanks! I found the problem - the red wire for the charge line got pinched by the support bracket for the tow plate. Everything is fine now. Thanks again.