Routing a Trailer Wiring Harness Power Wire to the Battery on a 2016 Subaru WRX

Published 12/12/2015

Products Featured in This Question

Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector

(49)

$62.67

Deka Cable Ties Kit - UV-Resistant - Black - 50 lb Tensile Strength - 11" Long - Qty 25

(41)

$2.83

Question:

How the heck am I supposed to run the hot lead up to [my] car batteryinch quickly and easilywithout making a real mess of things?

asked by: Steve S

Expert Reply:

There are several different methods you could use to route the power wire from Curt trailer wiring harness # C56259 to the battery on your 2016 Subaru WRX.

The first step is to find the best exit point from the trunk/cargo area. There are 2 paths you could take. First, you could check for a grommet or some exit point beneath the flooring through which you could route the wire.

Or you could come into the cab of the vehicle from behind the rear seats.

The next steps are going to depend on which route you took. If you ran the wire down through the bottom of the cargo area then you can pull the wire down and route it along the frame or another harness all the way up to the front of the vehicle using wire ties such as # DW05726-25 to hold it up. Avoid areas that could pinch or burn the wire such as exhaust and suspension.

If you went in from behind the rear seats then it is fairly easy to run the wire along the perimeter of the interior and tuck it underneath the interior trim panels all the way to the front of the vehicle. Once at the front the wire could be routed through the firewall to get into the engine compartment. Look of other wires going through the firewall and try to use that point.

The last step is the same for either method described above. Route the wire to the battery, splice in the fuse holder (without the fuse in it), connect it to the positive battery terminal, re-attach the negative battery cable, and insert the fuse to complete the installation.

I have also included a link to a help article I wrote with tips on routing the power wire.