No brake light

[Guest]

1980 GS1100E brake lights not working. Sigh. Where to start?

This is TOM_MLC's old silver bike and some said - and I remember too - he had a flashing brake light system. But when he sold me the bike he said it didn't have it when I asked. Now a couple weeks later I realize the brake light is not working at all. Oh and neither is the left rear blinker, but at least that one is obvious, it is broken! Are these things related? I'm not sure. Behind the rear lens there are two bulbs, one over the other. The bottom has one filament and the top has two. Bottom bulb is fine. In the top bulb both filaments look good and one is lit when the key is on but the other does not light when either the front or rear brake is applied.

Any help you can lend is appreciated. The E is totally new to me as I came from the GL.

-Bob

[tkent02]

Got a multimeter?

[cowboyup3371]

Got a spare bulb just to make sure that one didn't blow?

[littleroot]

Got a multimeter?

Yes I do. Two in fact, one too/more complicated

[littleroot]

Got a spare bulb just to make sure that one didn't blow?

No i don't... unless it is the same as in the GL... good idea

[GateKeeper]

take bulb out, and test directly with holding it to the battery, see if it lights up, you will need a piece of wire for either the negative or positive, the bulb itself can be contacted directly to the opposite, or as in the picture below

[littleroot]

Got a spare bulb just to make sure that one didn't blow?

The bulb is confirmed good: I swapped a bulb with my GL and the problem stayed with the E bike.

Rats. I wish it was that easy

[littleroot]

take bulb out, and test directly with holding it to the battery, see if it lights up, you will need a piece of wire for either the negative or positive, the bulb itself can be contacted directly to the opposite, or as in the picture below

Great diagram, Thanks!

The bulb checks out OK: I swapped it with the one in my GS1100GL.

Unfortunately I have to go digging in the wires I guess. Where to start...?

[littleroot]

Of course the darn dash board system shows the stop light as good

[GateKeeper]

so no brake light comes on, when ? if you pull the brake lever on the handle bar does it come on ? if you push the brake lever via the foot pedal does the light come on ?

in either case each one has a switch that sends a signal to activate the bulb, are those in working order ? now that we have determined the bulb is OK

[tkent02]

Got power?

[littleroot]

so no brake light comes on, when ? if you pull the brake lever on the handle bar does it come on ? if you push the brake lever via the foot pedal does the light come on ?

in either case each one has a switch that sends a signal to activate the bulb, are those in working order ? now that we have determined the bulb is OK

That is right: no brake light comes on. Both the front brake and rear brake switch do the same: no light comes on. Headlight works, three out of four turn indicators light up (fourth turn indicator is in the mail). Bike starts and runs just fine. Just no brake light.

[littleroot]

Got power?

Seems like it. Bike starts, and runs great. Just rear brake light does not come on when you use either front brake lever or rear brake foot lever

[GateKeeper]

do you have this and are they in good condition

[littleroot]

do you have this and are they in good condition

I cannot say for sure it is in good working condition but what are the odds both the front brake and rear brake switch failed at the same time?

Yeah, so I am ruling out the hand lever switch and foot lever switch for now, but maybe I'll be sorry I did!

I just traced the brake light wires back to a box and the name on it is "Priority Plus", which Google says is a flashing brake light kit. So it is indeed still installed. I think I should bypass it. Opinions?