'79 kz650B3 Starter Works but No Lights?

Electrical system question, any help is appreciated.

I've got a '79 kz650B3, it was sitting in a barn for years, I just got it running. (see profile pic)

The bike starts right up but none of the lights work except the hazards. I replaced the ignition switch (no keys). There is power to the main fuse but not the headlight or taillight fuses. When I put a jumper from the battery to the headlight or taillight fuses, then the lights and everything turn on.

So, is my problem somewhere in the new ignition switch? It was an Emgo and it supposedly fits many kz models.

I was also wondering about the Rectifier/Regulator, but if that was bad there wouldn't be power to the starter solenoid either right?

Thanks in advance!
Warren

fuckin emgo... my problem was VERY close to yours... and first off... i can let you know that emgo does NOT offer blank keys... and it took me a week to figure out a solution to MY key problem... well.. my local "Do it best" actually cut a nissan car key... it fits.. it works... better spending $3 than $40+ for a new EMGO......
my NISSAN key has 2 call letters on it.. "X123" and "DA25".... and mine is on an 81 kz750 h2 ltd...

LIGHTS???? i only had half of your problem... my tail light wouldn't work... and i jumped the tail light like you did.. and it worked.... but... my headlight already worked... soooo i spliced the power off the headlight (cuz i only want that tail light on when the key is "on")... my brake light worked no problem.. and i could tell that there had ben some mods in the wiring from the tail light because it had an alternate power source.. all the positive connections were bad in the back of the bike... soo... like i mentioned.. my headlight worked already... so i just ran a new wire from front to back.. i couldn't find a working power source on the back of the bike...

you can find wiring diagrams for your bike for free... sooo i'd look at that... if you're good with wires like me (sounds like you are)... you can just start running jumps from wires to find out if they're gonna work for you when the key is on.. i'd start right out of the plug for that ignition switch you installed.... start finding a good source and run new wires if you can't get anything else to work...

lemme know if you have more questions i might be able to help a little more...

Did the Emgo Ignition have the same white plug as the old Ignition ?
Do you still have the old ignition but no key?
If you can find the key code # on the ignition beside the keyhole, or somewhere on the back, I can cut you a key for it.
It will probably start with a Z and four numbers.
The key code number may also be stamped on the seat lock.

Wiring diagrams for the 650 can be found here:
diagrams.kz650.info/index.htm

w777h wrote:

Electrical system question, any help is appreciated.

I've got a '79 kz650B3, it was sitting in a barn for years, I just got it running. (see profile pic)

The bike starts right up but none of the lights work except the hazards. I replaced the ignition switch (no keys). There is power to the main fuse but not the headlight or taillight fuses.

The EMGO ignition switch for the 1979 KZ750B models does NOT work correctly (makes the wrong connections). I bought one and ended up desoldering the wires from the back of my old switch and connecting it to the new one. I had to Ohm out the switch contacts and connect the wires as needed. Being an electrical engineer came in handy.

duplicate

soccerd31 wrote:

you can just start running jumps from wires to find out if they're gonna work for you when the key is on.. i'd start right out of the plug for that ignition switch you installed.... start finding a good source and run new wires if you can't get anything else to work...

Rather than cut into the harness, use the old connector and solder it to the new switch. There were plenty of switch contact terminal sets on the new switch to get it to work.

Yep, it was the damn switch. I had to de-solder it and move the wires around on the back of the housing.

Almost everything is working now, still no turn signals but the hazards work and the turn signal flasher works so I'm sure it's not a huge problem.

Thanks for all the help.