Can Brake Controller Wiring be Added to 2021 Jeep Grand Cherokee

Updated 01/12/2026 | Published 01/07/2026

Products Featured in This Question

Wiring Kit for 2, 4, 6, and 8 Brake Electric Trailer Brake Controllers

(166)

$46.44

Question:

I have a 2021 jeep grand Cherokee 80th anniversary edition, it did not come with a factor tow package, the dealership installed a Mopar Reese hitch with the four post and seven pin trailer hook up and the needed harness to hook into the factory wiring, all Mopar parts, I am needing to install a brake controller, but how would I go about hooking into the factory harness since I do not have the plug that’s underneath the dash? Does Mopar offer a plug to access that or do I need to direct wire everything?

asked by: Jeff Y

Expert Reply:

Hey Jeff, hardwiring a brake controller like the P3 part # 90195 to the 7-way directly is certainly an option but a Mopar dealer might have a way to complete the brake controller wiring under the dash so that you could use it to install the brake controller a bit easier. You'd have to check with them for that though. If you have to go the hardwire route though you'd want the part # 5506 for that. If you talk to them let us know what they say and we can go from there to find best way to go.

expert reply by: Jameson C

Jeff Y.

1/9/2026

I contacted the dealer, they do not offer a plug harness to tap into the factory for a trailer brake controller, so I guess a direct line would have to be ran correct? What would you suggest be the best route for me to go since it is already wired into the factory rear harness?

Jameson C.

1/11/2026

@JeffY You would want the part # 5506 I mentioned earlier then. This comes with wiring for the brake controller up to the battery as well as for back to the 7-way.

Jeffy

1/12/2026

@JamesonC yes