Trailer Brakes Lock Up When Brakeaway System is Wired In

Question:

98 Thor Tahoe. Just got this recently and went to go on a trip,connected to truck and when we went to pull away trailer brakes locked up.Checked connector wiring,all good,as were brake controller etc.Finally disconnected trailer battery and heard brakes release.Re-connected truck,brakes now work fine,adjustable etc.Checking wires on breakaway switch,have 12v. Is the breakaway switch bad? Rest of trailer wiring is visually good,no obvious defects or rub through.All advice welcome. Thanks.

asked by: Colin H

Expert Reply:

It does sound like there is a problem with the switch or its wiring. The pin might be pulled as well. When the pin is pulled the metal contacts inside will touch and complete the circuit. Corrosion could also cause a short inside the switch.

It sounds like the easiest solution is to replace the switch. Really any switch will do unless your system takes a special switch. The most popular switch is # HM20010.

expert reply by: Michael H