How do you install a brake controller in 2007 GMC 2500HD?

Answer 1

Trailer Connections

figure 13

figure 14

figure 15

figure 16

figure 17

figure 18

TRAILER BRAKE CONTROLLERS

Here's how to connect a trailer brake controller to the 2007 Silverado and Sierra pickups. These instructions do not apply to trucks with option JL1 (Integrated Trailer Brake Controls) available on H.D. trucks for 2007. Also, trucks with option TP2 (H.D. availability) already have the 12v battery trailer feed used as part of that RPO.

This hookup is entirely different from the earlier Silverado Classic and Sierra Classic.

TIP: The owner manual (page 483) refers to 4 wires, but there are 5 wires looped back in the IP harness. The fifth wire is not required with most systems (see table below).

1. Locate the trailer brake control circuits looped and taped to the main harness under the IP (fig. 13).

2. Pull the trailering wire harness down.

3. Match vehicle harness label circuit functions to the trailer brake controller jumper harness functions (fig. 14).

TIP: Match functions. The colors of wires that are to be joined together may not match.

VEHICLE HARNESS FUNCTIONS Wire ColorFunction Dark Blue Switched power from controller to trailer brakes Red with Black Stripe Fused vehicle power to electrical brake controller Light Blue with White Stripe Brake switch input to power electric brake controller White Ground Orange CHMSL (not required with most systems) 4. After completing the under-IP connections to the electric brake controller, open the hood and locate the red wire taped to the harness between the under-hood electrical center

(fig. 15) and the driver side front fender.

5. Break the tape on the red wire and pull the wire toward the front of the vehicle.

6. Remove the cover from the electrical center.

7. Place the terminal on the larger of the two studs (fig. 16) at the front of the electrical center and secure with an M8 nut.

A Location of larger stud

B Existing fuse

TIP: The fuse is already present in the vehicle to power the electric trailer brake controller system.

AUXILIARY 12 VOLT FEED TO TRAILER

This hookup may be used operate electrical devices in the trailer -- for example, a refrigerator or a battery charger.

1. Locate the red wire looped and taped to the chassis harness below the brake master cylinder (fig. 17).

2. Break the tape and route the wire to the front of the vehicle under-hood electrical center.

3. Place the terminal on the smaller of the two studs (fig 18) on the electrical center and secure with an M6 fastener.

A Location of smaller stud

B Install fuse

4. Install a 40 amp fuse to power the circuit.

TIP: Devices powered by this fuse will drain the vehicle battery if left connected with the vehicle not running.

- Thanks to Steve Love