Brake Controller Installation on 2008 Grand Cherokee Diesel

Published 12/27/2012

Products Featured in This Question

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

(164)

$57.19

30 amp. In-Line Circuit Breaker - Perpendicular Mount Bracket

(74)

$7.29

Hook Probe Circuit Tester

(66)

$14.40

Question:

what do i need to do to get electric breaks on this Jeep, it has factory 7 pin. a blue wire? or a green wire? where do i start ? i am lost . please help. 2008 with the Mercedes diesel. CDR everything is electronic.. dont want too touch the wrong wire and have some module go pop....3000$ later.... that was a bad idea . thanks for any insight.

asked by: George S

Expert Reply:

According to my contact at Tekonsha, there is not any special procedure or considerations for a brake controller installation on Diesel equipped models versus the gas-engined counterparts.

To install your brake controller, you will look for a light green wire bundled up under the dash or behind the driver's side kick panel that would be next to your left foot while driving. This wire will connect the brake controller output (blue wire) to the 7-way. The power (black wire), ground (white wire) and brake lamp stoplight switch wire (red wire) would all need to be connected.

You can use one of our kits, part # 5506 to install your brake controller. The kit includes a length of duplex cable to reach from the controller to the battery. The black wire connects to the positive battery terminal via a 30-amp circuit breaker that is included in the kit and the white wire would ground to the negative battery terminal. The red brake controller wire connects to the brake stoplight switch located at the top of the brake pedal. The stoplight switch will have several different wires exiting it, you will need to use a circuit tester like part # 40376 to find the wire that only shows voltage when the brake pedal is pressed. Once you locate that circuit, tap the red wire into it.

If you have not already purchased a brake controller, I would recommend the Tekonsha Primus, part # TK90160. The price difference between it and the Hayes controller you mentioned is minimal, and the Primus is a much better controller that you would be much happier with.

I will link you to some FAQ articles that should help with the installation.

expert reply by: Mike L