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Trailer Brake Controller Installation - 2008 GMC Sierra

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GMC Sierra Brake Controller

Installation of a Brake Controller for a Trailer on a 2008 GMC Sierra

Today we are going to be installing a brake controller on this 2008 GMC Sierra. The part number is 5520, along with the 7-way replacement socket for the GM products, part number PK11916. We are going to start in the rear, installing the 7-Pole replacement socket. We are back behind the bumper here and if you can see this unit here is actually the 7-pole factory socket that we are going to be plugging into. So we want to go ahead and disconnect this off of the knockout that goes into the bumper. We are back on the outside of the bumper here and this knockout here is actually going to be removed. This is where the PK11916 is going to be put in place of. Now that the knockout is removed, we want to go ahead and put the replacement socket in there. It just slides in and you want to line up the notches and just rotate it and it locks right into place. I am going to take the socket that we removed from the backside of the knockout earlier and plug it into the back of the 7-way here.

And we are back behind the bumper now. As you can see, the socket that we removed earlier and plugged back into the back of the PK11916. We are back inside the cab now, down below the steering column down by the brake pedal. If you look up under here, you can see a bundle of wires taped up with this white tag. This is going to be the bundle for our tow package for the brake controller itself. We want to cut those wires down to give us a little more room to work with. Alright I went ahead and pulled all the wires out here and the brake controller that we are using is going to require you to purchase a universal plug as well, the 20127. It is going to have the 4 loose wires here. We are going to connect the red wire here off of the GMC into the black wire. The dark blue is going to connect to the dark blue. The light red on the harness here is going to connect to the light blue. Once the connections are made, I am going to go ahead and tape them up with electrical tape. OK, now that we have the plug wired in, we just want to find a suitable mounting location for the mounting bracket.

Typically you want to mount it to the right side of the steering column, somewhere in this area, somewhere where you can easily access it in an emergency braking situation. On this particular GMC, there is actually a roll under flange here on the bottom side of the dash that will allow the brake controller bracket to sit flush here. And that will make a pretty good mounting location there. That is where we are going to go ahead and mount it. With the brake controller now mounted in place, you want to go ahead and route the wires up into an area where you are going to be away from anything that is hot or moving, such as the brake pedal, the gas pedal, etc. We just want to go ahead and plug into the back of the unit. Once we have it plugged in, we want to go ahead and zip tie the excess wires up and out of the way.

We are under the hood now. We need to finalize the connections for the brake controller. We are going to have to actually remove the cover here for the fuse. There are going to be 2 wires that we need to connect. The first one is the power feed for the brake controller which is located right here on the side. We are going to run that directly to this post here. The accessory power 12 volt feed, which is right here with the ring terminal. Again it is taped to the harness here and we need to cut the tape and it is going to run directly to this post here. The ring terminal for the brake controller here is actually going to go on the far post. The ring terminal for the hot lead, the 12 volt lead for the plug, is actually going to go on the far post over here. For these posts, you are going to need to proved your own nuts to tighten these down. You will also need to fuse these as well. The post for the brake controller needs to be fused with a 30 amp fuse. The post for the hot lead will need a 40 amp fuse. This concludes the installation of brake control part number 5520 on a 2008 GMC Sierra.

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