Trailer Brakes Do Not Work on a Trailer Towed by a 2001 Chevy Silverado
Question:
I have a reliant brake controller installed on my 2001 silverado. Everything works on my travel trailer except the brakes . The brake lights work but no brakes.
asked by: Jim B
Expert Reply:
If you have just installed the brake controller, the most likely issue is that there are some connections that need to be made under the hood of the truck to make everything fully functional. I have included a link to an FAQ article that covers this for you to view.
If this problem suddenly appeared after it had been working fine, the first thing I would check is the trucks stop light fuse or center high mount stop light fuse (CHMSL). If the third brake light fuse is out, that would cause the brakes not to work on the trailer because the brake controller uses a dedicated brake light signal to tell it that the brakes are being applied. This is the likely cause especially if the brakes do work when you apply the manual override.
The trailer brakes and brake lights are on separate circuits from the 7-Way trailer connector so the 2 are not related. But the brake light circuit on the truck is related to the controller as explained above.
If you have everything connected and all the fuses are intact, and the controller is still not activating the brakes test the controller to see if it is providing power. To do this, sever the blue wire behind the controller a few inches and use a circuit tester, like # PTW2993 if needed, to test the end coming out of the controller. it should show power when you apply the manual override.
If it does not, then make sure that there is power on the black wire to the controller. If there is not power to the controller, then there is a missed connection or missing fuse under the hood as explained in the FAQ. If the controller has power but will not send a signal on the blue wire, then there is something wrong inside the controller and it will need to be replaced.
If it is sending power on the blue wire like it is supposed to, reconnect the blue wire that was severed and then test the brake output pin on the 7-Way. If no power is coming out there then you may need to run a wire from the trailer connector brake pin under the truck and into the engine compartment and connect it as described in the FAQ. Or you can route it through the firewall into the cab and connect it directly to the blue wire coming out of the controller.
If there is a proper connection from the 7-Way to under the hood then there may be a nick or break in the wire that you will have to hunt down and repair.
If power does get back to the 7-Way then the likely culprit is the trailer. Start by checking the main trailer ground and the brake magnet grounds and make sure they are attached to clean and corrosion free bare metal surfaces. You an also further test the brake magnets by following the other FAQ I have linked for you.
