How to Complete Hardwire Installation of Hayes Synchronizer Brake Controller

Question:

Need a hard wiring diagram with each wire being Identified plz

asked by: Nina B

Expert Reply:

I'd be happy to assist with that.

In addition to the # HA81725 Hayes Synchroinizer brake controller, you'll need a universal wiring harness, part # HA81789-HBC and our Brake Controller Installation Kit, part # ETBC7. The kit includes everything necessary to install a brake controller in your vehicle, with the exception of the controller itself and a 4-pole trailer wiring harness for the vehicle.

If you click the provided link, you can see some FAQ articles about installing a brake controller, which include the wiring diagram you're asking about.

The black brake controller wire connects ultimately to the positive battery terminal, via the 30 amp circuit breaker included in the installation kit. The white wire grounds to the negative battery terminal. The blue wire carries the voltage from the controller back to the trailer connector, and ultimately to the trailer brakes. The red wire connects to the brake stoplamp switch. The switch is located at the top of the brake pedal on most vehicles. There will be several wires exiting the brake switch, so use the voltage tester from the install kit to probe each of the wires until you find the one that shows voltage on it ONLY when the brake pedal is pressed (not with the turn signals, running lights, etc).

expert reply by: Mike L