Third brake light

[steverkemp]

On my DX3 the third brake light blinks when my hazards are on. Likewise, when my hazards are on my brake controller pulses on and off. My dealer told me that’s just how it is but it drives me nutty. Can someone tell me why this is?

[bclemens]

Likely because the signal wire is coming off of the brake lights. So when the brake lights flash, it is sending a signal. The 3rd brake light would be a good thing I think...the brakes, make not as much.

When the hazards are on, I am guessing you are going slow, can you disengage the brake controller?

[steverkemp]

Brian, yes, slowing down or stopped. I’m not sure I know what you mean about disengaging the brake controller.

[bclemens]

I don't know either..I never tow. I just know you can adjust them....wasn't sure if there was a way to turn it off.

[RV Randy]

Originally Posted by steverkemp

On my DX3 the third brake light blinks when my hazards are on. Likewise, when my hazards are on my brake controller pulses on and off. My dealer told me that’s just how it is but it drives me nutty. Can someone tell me why this is?

Is this the factory installed brake controller? I can't remember, what type & brand is used? Is the unit turning on and off when the hazards are blinking, or is it applying the trailer brakes on/off when hazards are blinking? I haven't checked mine yet, but some people were saying the brake light comes on when the Jake brake is activated even if your foot is not on the brakes, so you would probably see the trailer brakes being applied then too.

If the unit is electronically triggered to apply the trailer brakes from the electric brake light switch, then it may be wired wrong i.e. picking up the brake sense voltage from the wrong point. Or, the FL chassis may be wired different from most cars and light trucks that apparently use a different circuit to flash the hazards. I would call the controller mfg and ask them if there is a work around for the issue.

The other option is to replace the controller with a higher end unit that has built-in accelerometers in it that sense the tow vehicle slowing down and use that to trigger the trailer brake application instead of brake light voltage. Those units will also potentially apply the trailer brakes when the jake brake is active if its slowing the vehicle noticeably.

I need to check this out on mine too. In Colorado its pretty common to be on long downhill grades in the mountains where you are in the right lane with your hazards on, locked into a lower gear and using the jake brake to keep your speed under control. It would NOT be good if you had to turn your brake controller off in that situation. It would also be bad if the brake controller is applying trailer brakes via the hazard flashers as you could over heat and lose trailer braking.

[bclemens]

We install a Prodigy...I think a 2, maybe the 3.

[RV Randy]

That one is electrically triggered, also has an inertia sensor to detect panic stops and increase braking. I think the OP should call the mfg (Tekonsha?) to see if this is a known issue and if there is a solution.

[steverkemp]

I called tekonsha and they said they make a $50 pulse preventer that wires in by the brake controller to prevent hazard lights from pulsing the brake controller.

For other M2 owners, does your 3rd brake light flash when hazards are on? You would think FL would have a dedicated brake only circuit.

[FOURWHL]

I'm not sure on the 3rd brake light but my controller definitely pulses.

I need my gain all the way up on the MH so the little pulses dont do enough to actually actuate the brakes from what I've seen. Only hits 2 or so iirc. Nice to know tekonsa has something though. I haven't used the hazards enough to be bothered by this.

[DR Quest]

I have also seen my controller pulse with the flashers on. I use air for my brakes on my toad so never thought too much about it. Never seen my 3rd brake light flash.