I have an intermittent brake light problem that just started yesterday on my '07 Ultra. Yesterday I noticed that my cruise wouldn't engage. My first thought was brake light and I was right, the brake light was stuck on. When I would turn off the ignition, then back on again, and apply the front brake there was no problem, apply the rear brake and it would stick on. I assumed I had a bad rear brake light switch. No big deal.

Fast forward to today, I go out this morning and can't get it to stick. After riding for an hour or so, sure enough, it's stuck. I ride straight to the closest dealer and show the service writer. This time though, applying EITHER brake will cause it to stick on. They roll it in to wait for an available tech, takes about 1/2 hour to get it in the back. Normal operation, cannot duplicate the problem. WTF do the front and rear brake switches have in common besides the darn bulb? And why is it not happening all the time? Ideas?

 

You said that the brake light switch was stuck this morning. Did you actually look at the switch and see that it was physically stuck or did you just see that the brake light was still on after you let go of the brake pedal?

I find it hard to believe that both the front and rear switches are failing at the same time. Both switches ultimately feed power through the same wire to the brake light. My guess is that you have some frayed or pinchen wires in the harness that feeds the brake light.

Do you have a Run/Turn/ Brake modual? If so, it may be failing or thwireing for it may be the source of the short.

 

No, the light stays on but I can't actually see a switch that's stuck, and like you, I seriously doubt that they'd both fail at the same time. No run/turn/brake add-ons either.

 

Is the bike throwing any DTC's?

Carl

 

Nope. No codes. Someone suggested the brake relay, makes sense and I'll start there.

 

Is it possible your controls have wiggled/moved just a bit? Just making sure the front brake lever is holding the brake switch in all the way. I am sure you know this but the lever has to hold that plunger all the way down or the brake light will kick on with the slightest movement. I ran into this after my bar change. I could bump the handlebars the the brake light would stay on.

 

Yeah, that's not it. The problem originally started with the rear brake and now is both, but only when hot.

 

i would suggest replacing the rear brake light switch.

 

Have you replaced the levers or had them off? If so and you didn't shim front brake lever like the srervice manual states then you've screwed up your front brake light switch. It's fun to replace.

 

Nope, last time they were apart was many thousand miles ago. My gut says brake relay, that's where I'll start.