Strange brake light problem

On my 81 XJ650 maxim.
The tail light works, the signal lights work but not the brake light.
I've checked the bulb and changed it.
I've checked the wiring connections, all solid, all read well on the multi-meter. But when I press the brake pedal or pull on the front brake lever, nothing, no brake light.
Any suggestions would be appreciated.
thanks,
baz

 

check your brake light switch, for the rear brake its a small plastic housing with a threaded screw and a wire connecting to it inside the frame slightly behind the pedal on the left side. When you depress the brake pedal, it _shoud_ pull the switch down and activate the brake light. Clean the connections with some contact cleaner...same thing for the front brake switch assembly. If that don't work, pull it apart and ensure you are getting proper voltage to it.

 

okay, thanks, will do.

 

Weight the Pedal
Secure the Brake Lever
Tape the Probe of your Test Light so you won't short-out as you Test the "Contact Spots" at the bottom of the Bulb Sockets.

If you have juice.
Check that the Spring-loaded base those Contact Spots are on isn't stuck at the push-back spot and not making contact with the Bulb when the Bulb is twist-locked into position.

 

I touched the test light to the two contacts on the spring loaded base and they both light up. I also pushed it in and out several times and it does make contact with the bulb. It's when you hit the brakes that the other contact doesn't work. Weird. It works on the test light but not on the bulb itself. So I'm guessing there's a ground somewhere that's not connected. Is that about right?
thanks,
baz

 

Follow the wires coming from the Tail Light Pigtail to where they plug into the Main Harness.

Check to see that the Tail Light lead and the Brake Light lead are not reversed.

Yellow to Yellow
Blue w/ Red to Blue w/ Red

 

That all checks out. I have to check again but I think that both filaments in the tail light are on all the time, meaning the brake light is on all the time. So that would be one of the two switches being stuck in the on position, right?
thanks,
baz

 

There are two switches involved in your brake circuit, one on the right handle bar cluster and the other lives in a hole at the back of the motor, just behind the right side. I find both the switches broken often on these bikes. The handle bar switch is not adjustable but the rear brake switch is. You ought to pull the rear switch and give it a good cleaning and and adjustment. I've found a few of these switches melted shut so that is a good candidate for your problem. They are cheap, something like $15 from Chacal so don't worry about finding a replacement should you need it. I keep a few laying around as spares given their track record with me.

 

Thanks for all the input, Rick.
Yup, it was the rear switch. I think what happened was that vibration turned the switch in its threaded base just barely enough so that it stayed on.
I only noticed today that both filaments on the tail light remained on all the time.
So I adjusted the switch and the spring and now it's fine.
DOH!
Of course that's what I should have checked in the first place, THE SIMPLE STUFF!
Oh, well, ya lives and ya learns.
Thanks again for the tip that led me to the problem,
baz

 

Rig the Rear Brake Switch to come-on "Early"
That way ... you can tap the brake pedal without engaging the brake to have tail gate drivers give you some room.