Saturday, November 5, 2011

Summary of 7-pin tow harness installation on a 2008 Nissan Pathfinder


On the off chance that someone stumbles acrossthis blog and wants to install a 7-pin towing harness on a Nissan Pathfinder, here is a summary of what I had to do and what it cost.


The installation itself is very straight forward. It is mostly just a matter of
plugging in a couple connectors under
the rear of the Pathfinder and bolting on the plug. I don't have much
skill/experience with automotive repairs/alterations, and this
was a fairly easy project, even for me, taking only about 45 minutes. The following instructions that I found on the web were extremely helpful:

Photo Installing OEM 7 min trailer wiring harness on a 2005 pathfinder - Nissanhelp.com Forums
Relays are located in a box under the hood.
Locations for Towing relay 1 and 2.
The second relay is not installed yet.
The 7-pin harness also requires 2 towing relays installed near the battery of the Pathfinder. Surprisingly, they do not come with the harness. One of them (Towing relay 1) was already installed, presumably to activate the lights, signals, etc. for an existing flat 4-pin harness, but I also needed the second relay to activate the full functionality of the 7-pin harness, specifically, the charge wire. I purchased Towing Relay 2 (Part number: 25230-7996A, $38) from a Nissan Dealership here in Boulder, plugged it into the socket next to the tow vehicle battery, and now the charge wire is active when the truck is running.

Total cost for the 7-way tow harness and second relay was ~$105 with tax, but I'm pretty sure this could have been done for less if I hadn't gone through the dealership and if I had bought the parts off the web instead. Also, of course, I had to install a brake controller to operate the trailer brakes, which was a separate project.

Anyway, that is about it. Pretty simple once I tracked down the parts I needed. Hopefully this information will save time for anyone else installing tow wiring on a Pathfinder.