Topic: Brake light not working. Recommendations?

[dpuma8]

I have a new to me 1971 CB750. It runs well except the brake light is not going on and is confusing me.

When I turn the key to the left, the brake light is on. When I turn the key to the right to where I can start it, the brake light does not go on at all whether I squeeze the front brake or push down the rear brake. When I turn on the headlights, the brake light does not light up either.

The PO said the brake lights worked when he sold it to me a month ago but since I can't ride at night with my permit, I can't really remember if it was working or not when I got it.

Any suggestions as to what I should look at? How can I test what might be wrong?

[KingCustomCycles.com]

Switch position controls parking/running light not brake.  Maybe just a bulb burnt on the brake side. 

[Johnie]

If you have a tail light and no brake light could just be a bad bulb. There are 2 filaments in that bulb. One for running light and one for brake light. Maybe just the brake light filament is out. When you remove the bulb check the socket for corrosion. Last could be the brake light switch, but I don't see those go bad very often. Oh, welcome to the forum...got any pics of your ride? We like pics here...

[dpuma8]

Well, the thing is I don't have running lights when I put the headlights on. This isn't the same bulb as the brake bulb, right? The bulb only lights up when the key is turned to the left. I will take apart the back light and see if something is wrong (fairly clueless with wiring).

I will post pictures soon

[MrGardman]

When you say running lights, do you mean you have no tail light on? If this bike has standard controls on it you should have a tail light lit up when you move the right handlebar switch to low beam or high beam. And from there when the ignition switch is in the run position you should have the brake light portion of that bulb come on when you use the front brake lever or the regular foot brake.

[dpuma8]

When the headlight is on, the tail light is off.

When I push the brake, the tail light is off.

When the key is turned to the left, the tail light is lit but it doesn't get brighter when I hit either brake.

[Spanner 1]

Tail-light fuse ( 5A ).... in 'Park" position taillight gets power from Main fuse = works O.K.

[dpuma8]

I took apart my light and it is a LED so there are no bulbs to change unless I change the whole board.

(http://www.amazon.com/Motorcycle-Integrated-License-Bracket-Nighthawk/dp/B0056DLKZK)

 This is very frustrating because I followed the Green wire with the yellow line and everything is connected.  I don't see a 5 amp fuse but I do see a 15 amp fuse and the fuse is fine.

Just to be sure, it can't be a brake switch problem if neither brake triggers the rear light, correct?

If I can't figure this thing out, how much would I expect to pay to get my wiring fixed?  Is there a way to check with a multimeter? How would I do it?