Troubleshooting Voyager Brake Controller That is Not Reading Trailer

Question:

Will the brake controller be destroyed if the brake magnet is grounded to the battery in addition to the chassis? I did that to get the proper 3 amps to the magnet and now the blue wire always has 12V on it with no brake applied and the green light no light will not turn on. The controller is still getting 12V at the black wire. Thanks.

asked by: Chad

Expert Reply:

First of all, grounding the brake magnets to the negative pole of a trailer mounted battery as well as the trailer frame is fine. The negative battery terminal should be grounded to the trailer frame anyway. You should check all grounds, starting on the tow vehicle. Also check that the connector on the trailer is grounded to the trailer frame and that each brake magnet is grounded to the trailer frame. All grounds should be tightly connected to the trailer frame, remove any corrosion so that there is good metal-to-metal contact.

The green light not coming on indicates that the controller is not reading your trailer for some reason. The fact that you are getting a constant output on the brake wire could indicate any number of problems. You can sever the blue wire right behind the brake controller (be sure to leave enough wire to reconnect it). Test the controller using a multimeter like part # PT89ZR. You should be getting 12 volts when the manual braking switch is actuated and the controller is turned all the way up. Reconnect the controller.

Check the trailer connector on the vehicle. Test the brake pin (5:00 position on connector) while manual switch is activated, you should read approximately 12-volts. Closely examine the pins of the connector for green or white corrosion, and clean as necessary. If corrosion is severe, check the terminals on the rear of the connector where the wires attach. A build up of corrosion can cause one terminal to short out on an adjacent terminal.

Check the items I mentioned above, and get back with me to let me know what you find.

I have linked you to our Brake Controller Troubleshoot FAQ article that might also be helpful.

Check the connector on the trailer for corrosion. Trace the blue wire back from the trailer connector, looking for pinched wires or cracked or worn wire insulation that would allow the interior copper conductor to short out to the trailer frame.

Are your brake magnets is good condition? If you look at the face of the magnet, and the magnet is worn away to the point where you can see the copper wire that is encased in the magnet, the magnets are excessively worn and should be replaced.

It sounds like you might have two separate issues happening at the same time, a poor ground connection in the system and a short on your brake output circuit.