I recently put a smoked laydown tail light with a red led bulb on my bike and now the brake light doesnt get brighter when the brake is applied. I put the original bulb back in and it doesn't change either. The light stays lit as a running light but just wont get brighter when the brake pedal is pushed. She's an 04 superglide. Any ideas? Im thinking it might be a brake switch or something like that but don't know where to begin looking for it. This is my second Harley but the first one I'm doing all the work to myself I can turn the wrenches just need a little help with where to turn them. Thanks for your help.

 

Have you checked if it lights up with the front brake pulled or the back brake? The front brake light switch does break fairly easily, not sure about the back brake light switch.

 

Did you rewire when you installed the taillight unit?
Compare your wiring to this diagram, it sounds like you have a wire missing, or you may have a bad brake switch, check wiring first.

 

All i did was unplug the original bulb and plug in the led bulb. But once i found it not working i pluged original back in and it didnt work either, in fact it got just a faint bit dimmer when the pedal was pushed which the led didn't do.

 

Have you checked your fuses? The brake lights run on the accessory fuse on your bike.
Also, an LED lamp will not work on your bike without a load equalizer of some kind.

 

Ok I called to company that sold me the led. He told me that the led brake light doesn't require a load equalizer only turn signals do to slow down the flash rate of the led. He thinks it was a bad bulb and is sending me two new bulbs at no charge!! What a great company!! They are are called Sorgys out of Bastrop Texas. The only thing that still concerns me is the original bulb doesn't work either. I'm checking the fuses after work so maybe that's it.

 

My bad, was thinking about turn signals, I just recently made the switch and added brake and turn LEDs at the same time. That is great service, nice to hear of such companies.
The fact the stock doesn't work is a concern, I would figure that out before you install the new one.
Do you have a voltmeter?

 

Yes i do. You wouldn't happen to have a diagram of the fuse block would ya I can't find my owner manual?

 

Not handy, I am at work. Use the wiring diagram I posted above and check you brake wire while operating both brakes. If you have voltage you will know the fuse is good.

 

The front brake is dead right now. When I changed the bars it stopped working after it was dropped. The master cyclinder is full but wont push fluid to the caliper. I have a new one ordered so I will fix that soon. But when I took it off the bar there is nothing attached to the master cyclinder but the brake line. There are no electical lines to it at all so I don't think it has a pressure switch. I took the fittings out and worked the lever and it would not squirt fluid at all so I guess the pump died when it hit the floor. I still have rear brakes and did not mess with those at all it just doesn't kick on the brake light. I'll keep looking for my manual.