Tips for Routing a Trailer Wiring Harness through the Firewall on a 2017 Toyota RAV4

Updated 04/10/2017 | Published 04/09/2017

Products Featured in This Question

etrailer Trailer Hitch Receiver - Custom Fit - Matte Black Finish - Class III - 2"

(1508)

$167.44

Snap Bushing Grommet - 7/16" ID, 9/16" OD

(76)

$1.16

Question:

I decided I would rather run my hot wire down through the inside of my 2017 Rav4. Since I had back panel off , it was easier to run under doorsills to firewall. Your directions and videos were excellent. My only question is, where do you recommend I that I go through firewall at? Should I drill a hole for a grommet or is there a better access to the battery?

asked by: Jack L

Expert Reply:

If there is already a harness that goes through the firewall and that is easy to get to/work with then you can use that though it may require some persuasion to get the wire through. Otherwise drilling a small hole, running the wire through, and then sealing up the hole with silicone is the way to go. Just be careful not to drill through anything on the other side of the firewall!

What I recommend is to drill a hole a little smaller than 9/16 and then put grommet # SWC8055 in the hole. This will protect the wire from the sharp metal of the hole. Then seal it up after running the wire through.

expert reply by: Michael H