Red Light on Hayes Brake Controller Stays on and Drains Tow Vehicle Battery

Question:

I have a brake controler that has worked and went off after releasing the brakes..it just recently will not go off..and has been draining my battery...could it be faulty ?

asked by: Dave B

Expert Reply:

I am not sure which Hayes brake controller that you have, but in reviewing the installation instructions for the Hayes-Lemmerz Energize III+ Electric Trailer Brake Controller # HA81742B I found that there is a section that goes over if the "Controller red indicator on all the time."

The solutions they offer call for testing the Red wire and the Blue wire on the brake controller with a circuit tester like part # PTW2992. The Red wire connects to your Stop Light Switch and only receives power when the brake pedal is pressed. The Blue wire sends the braking signal back to the connector on your vehicle and tells the trailer when to activate the brakes. This wire should also only receive power when the brake pedal is pressed.

There are a few things you will want to check to remedy this. Start off by making sure that the break-away switch on your trailer isn't pulled. This will draw power to activate the trailer brakes in an emergency situation if the trailer were to come uncoupled. If that is secure then you will want to check the connector on both your trailer and tow vehicle. Check to make sure they are clean and free of debris or any corrosion.

The next step is checking the wiring itself. Follow the Blue wire from the brake controller and check for any places where it is damaged, corroded, bent, or exposed and fix or replace that section.

If you still are having trouble let me know and I can offer further assistance.

expert reply by: Jon G

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Michael B.

2/5/2020

I too have the red light always on my Hayes brake controller. I recently had both front and back brakes fixed on my tow vehicle. Could these repairs have changed the brake controller wiring? Thanks.

Jacob H.

2/10/2020

If the break controller is dim and increases to bright red the unit is operating the way it should. If the light is always dim or off you could have a ground issue with either the brake controller or the wiring itself. If the red light is on but you have no sign going to the brakes on the trailer then you might have an issue with your 7 pole wiring or faulty brake magnets. I would check these few things and let us know if there's anything else we can do to help.