Brake light always on!

[Travist1161732]

Hey all, have an issue. Recently switched all lights on the bike to LED's (so head lights, tail, front and rear signals). The issue now though is that the tail light is very bright, as if the brake is always on. The flash rate of the signals is faster than it used to be as well. The thing that makes me think it's the light and not the brakes, is that when I plug the bike monkey back in, it works fine. I have watsons for front signals, and regular 12V LED's for the rest. The tag light is not plugged in (but hasn't been for a long time). Any help appreciated. As background, the front brakes don't appear stuck, but the bike did tilt over on a trailer and I had to change the front brake reservoir (since it and the right clip-on took a hit) and re-bleed the brakes. Again though, it works fine when I plug the bike monkey back in (I have a race tail now so need a different tail light). So don't know whats going on.
-T


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[kismetcapitan]

that's weird, as I have exactly the same LED bulb setup. I'd recheck your brakes, including your rear - since the brake light is triggered by a pressure sensor, your brakes may actually be "on" very slightly. Might be an issue with master cylinder adjustment, either front or rear.

[Travist1161732]

Originally Posted by kismetcapitan

that's weird, as I have exactly the same LED bulb setup. I'd recheck your brakes, including your rear - since the brake light is triggered by a pressure sensor, your brakes may actually be "on" very slightly. Might be an issue with master cylinder adjustment, either front or rear.

I would totally agree, except I don't understand why it works fine when I plug the bike monkey light back in. I will keep looking at the brakes, but I'm not sure what to 'un-stuck' on them, since they seem fine otherwise.


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[freed929]

The led light have less resistance the causes the relay to cycle faster. Atleast that was my experience on my cruiser. I had to add a badland resister.


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[Travist1161732]

Originally Posted by freed929

The led light have less resistance the causes the relay to cycle faster. Atleast that was my experience on my cruiser. I had to add a badland resister.


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Yeah, on the signals right? But what about the brake light? Doesn't the ECU control output to the lights so that it's dampened while running and then full power when brakes applied. I think a resister would just dampen the whole thing? I'm not sure


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[viperclaw]

Are you using the correct wires for your brake light/tail light?

Are you saying you have a completely different brake light than the stock light?


Maybe the wires to the tail/brake light are connected backward? I believe there are only two wires going into the stock light and the ABS and instrument cluster control whether the brake light goes on or just the running light (it just changes the voltage to the light depending on what is needed).

[Travist1161732]

Originally Posted by viperclaw

Are you using the correct wires for your brake light/tail light?

Are you saying you have a completely different brake light than the stock light?


Maybe the wires to the tail/brake light are connected backward? I believe there are only two wires going into the stock light and the ABS and instrument cluster control whether the brake light goes on or just the running light (it just changes the voltage to the light depending on what is needed).

Ya, 2 wires only on the brake light (ground and positive). I tried them both ways. One way it lights up full force, the other way, nothing (no light at all). So only one possibility there. Not sure if the wires themselves are the issue, but a possibility I could imagine. My guess is that it needs a resister. What's weird is that the watsons are blinking at a faster rate than they were before I clipped the connector off the front low beam to connect the new lights (3 wires there, I assume one controlled the running light, I left that one disconnected, and the other two were the same as the taillight colors for ground and positive, so connected those and the headlights run fine). I wonder if the whole circuit has less resistance now?? I hate electronics...


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[viperclaw]

If you don't have Watson's in the front and back then the resistance will be off and the flashing rate will change. If you have a 2012 you can shut the bulb warning system off with the MENU function in the instrument cluster. Or on earlier models the dealership can shut it off. This makes the flash rate normal. Or put resistors in the other set of LED blinkers on the bike.

Just for shits and giggles have you tried hooking up the license plate light? Don't ask me why or how but it MAY affect it. It's pretty much the only difference in your set-up, no?

[Travist1161732]

Originally Posted by viperclaw

If you don't have Watson's in the front and back then the resistance will be off and the flashing rate will change. If you have a 2012 you can shut the bulb warning system off with the MENU function in the instrument cluster. Or on earlier models the dealership can shut it off. This makes the flash rate normal. Or put resistors in the other set of LED blinkers on the bike.

Just for shits and giggles have you tried hooking up the license plate light? Don't ask me why or how but it MAY affect it. It's pretty much the only difference in your set-up, no?

After discussing more with the vender, I think resisters were needed and not spliced in, so I'm going to put some in and see. I'm hoping this will solve it, I'll let you all know, thx for your input, as always appreciated

[Travist1161732]

Well, 20W 8ohm resisters on signals didn't work, still same flash rate (fast) and no brake light difference when pressed. Back to drawing board


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