Troubleshooting Faulty 7-Way Connector on a 2016 Nissan Frontier

Published 08/08/2018

Question:

My Hopkins 7pin/4pin flat adapter for the Nissan 2016 Frontier does not work. The LED test lights check out fine when plugged in to the truck end but when the trailer flat 4 is connected all test LEDs flash and there are no lights working on the trailer. The condition is the same with a similar Reese adapter. Any ideas as to what the problem could be? The trailer lights work fine with my 2002 Frontier which has a hard wired converter. The 2016 truck has a factory 7 pin T connector with all the OEM relays installed. Would changing to a 4 wire T connector solve the problem ? Thanks for your help

asked by: David M

Helpful Expert Reply:

Since you have used 2 different adapters and a different pickup that does seem to point towards the wiring on your 2016 Nissan Frontier as the problem.

I would try checking your connector for corrosion or debris and then your wiring; especially your grounds. If you are testing with an LED tester then there isn't much load being put on the circuits. Once you plug up your trailer it is drawing much more power (even more so if it has incandescent lights) which will expose any wiring problems that you may have.

If the connector, wiring, and grounds look good then you can have a shop check the wiring or install an aftermarket wiring kit to bypass the wiring on your Frontier. You can try a replacement plug-in harness like the Hopkins # HM43575 but I think the issue is further back than that if you can't see it.

Let me know if you end up wanting to bypass all of the wiring on your pickup and I can let you know what parts to get and link instructions for you.

expert reply by: Jon G