TOPIC:

My tail light is not working for my 1979 KZ750B. The brake light does come on though when i use both the foot and hand brake, but the tail light just dosnt come on, so i cant go riding at night. There is only one bulb and since the brake lights work im assuming its not the bulb, unless perhaps i needed a special bulb that has two diffrent light setting like low for the tail light and high for the brake (i wasnt the last one to replace it so i dont know what kind it is). But if thats not the problem maybe its the wires. There is a blue, red, Black&Yellow, wires all comming from the tail light so im assuming two are from the hand and foot brake and one is for the tail light. Any idea on the problem?

I was just looking more closely at my service manuel and it appears the yellow/black wire controls the tail light, and it also controls the blinkers, which have been behaving weridly. one would blink at diffrent intervals every time, and one would stay lit for like five seconds and then blink. DO you guys think these are related problems to one source or two diffrent problems

Tail light failure is probably due to a burned out filament in the dual filament bulb. Replacing the bulb usually resolves the problem.

The yellow/black wire is a ground wire.

The reported blinker problem may result from a weak battery or failing flasher unit.

Good Luck!

Strible wrote:

My tail light is not working for my 1979 KZ750B. The brake light does come on though when i use both the foot and hand brake, but the tail light just dosnt come on, so i cant go riding at night. There is only one bulb and since the brake lights work im assuming its not the bulb, unless perhaps i needed a special bulb that has two diffrent light setting

It's the dual filament standard auto bulb. I think the number is either 1034 or 1157 type at the auto parts store, can't remember which one.

Bulb type = 1157. The red wire is the running light POS. The blue wire is the brake light POS and the black/yellow is ground.

1. check filaments - brake light filament will be the longer of the two
2. the red wire comes directly off the ignition switch. Turn switch on and see if it is hot by using a multimeter. Pos probe on wire end and NEG probe on frame ground. If you have no 12VDC, then the ignition switch is the culprit OR the fuse is blown. It may be any of the three fuses... I can't remember which but if it is the main, nothing will be working.
3. Make sure ground black/yellow back in the tail light mini-harness is well connected although I don't think the brake light will work if the ground is bad.

is this it?


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