Common questions

How does GMC trailer brake controller work?

How does GMC trailer brake controller work?

A trailer brake controller uses electricity from the tow vehicle to apply a specific amount of power to the trailer brakes. It uses electrical circuits and trailer gain settings to regulate the amount of braking power. Some brake controllers have circuits that respond to the vehicle’s momentum while towing.

How to install a brake controller on Chevrolet / GMC 1999?

Hardwire the open wires of the brake control adapter to the wires on the brake controller. Plug the other end of the adapter into the electrical junction box (see above). Mount the brake controller in a place that is easily accessible. A: Remove the bracket in the corner closest to the driver. B: Remove the top cover of the “Accessory Fuse Block”.

Where do you run the brake wire on a truck?

Usually the wire is run either inside or above the frame on the driver’s side of the truck. Once run, connect the white (brake) and black (hot) to the blue (brake) and black (hot), respectively, on the back of the 6- or 7-way adapter.

Where do I plug in a brake controller?

The brake control adapter is plugged into the second slot from the left on the top row. Hardwire the open wires of the brake control adapter to the wires on the brake controller. Plug the other end of the adapter into the electrical junction box (see above). Mount the brake controller in a place that is easily accessible.

Where is the hot lead on a GMC 1999?

A 40 amp fuse needs to be placed in the last spot, closest to the post, to power the hot lead (see picture). If this post is already in use, you may connect the hot lead directly to the positive side of the battery via a 40 amp circuit breaker (provided in kit).

Hardwire the open wires of the brake control adapter to the wires on the brake controller. Plug the other end of the adapter into the electrical junction box (see above). Mount the brake controller in a place that is easily accessible. A: Remove the bracket in the corner closest to the driver. B: Remove the top cover of the “Accessory Fuse Block”.

Why does my truck brake not show power?

You can test the brake output pin and it should only show power with the manual override. If it shows power any other time then there is a short somewhere between the connector and the brake controller you will need to track down. If the truck side checks out fine then it could be the wiring to the brake magnets or the magnets themselves.

Why is my trailer brake controller not working?

This sounds like the trailer brakes are not receiving the signal from the brake controller when you apply the brakes. I believe what is happening is that you may have a loose, broken, or inaccurate connection on the red wire from the brake controller. The red wire needs to attach to the stop light switch above the brake pedal.

Do you need a battery for a brake controller?

No the trailer does not have to have a battery in order for a brake controller to work. The first thing I recommend to determine the problem is to clean the vehicle and trailer side connectors.

Author Image
Ruth Doyle