Ignition circuit diagram?

Just had a major snafu with my 1979 KZ650D this afternoon. Went home at lunch and picked it up, started well, then started acting funny on takeoff. Got it as far as the end of the block when it just stalled, no spark, no voltage getting to the coils. Bike has a Dyna S ignition, Dyna 3 ohm coils. Haven't had many problems with the electrical till now. Am assuming the circuit runs from the start switch to the starter solenoid, then on to the coils but not sure. I have checked the wiring as far as i can, but need a map before i go any farther. Also, the brake light blew as well as the low beam for the headlight, i am assuming at the same time as the ignition went.

Check the fuses?

Have a volt meter to measure for battery voltage throughout the wiring diagram (on the coils)?

All I have is the B3, C3 wiring diagram.... Maybe it will help....

Checked fuses, going to get a multitester to check voltage tomorrow. Weird that everything was fine then today, bam o voltage. Wiring diagrams for the B3 orC3 should work tho...

Check fuses with ohmeter/voltage on each metal tab... OEM Fuse holder blades may be your problem...

Voltage measurements the only true way to go about....

Good luck.... Most likely something simple.....

OMR

You can see a D model wire diagram, plus all other 650s here:
diagrams.kz650.info/index.php

I had the very same problem on an '82 KZ750. Couldn't go around the block without loosing all electrical power. Checked the glass tube fuses and they were just fine...what!? But when I finally checked the fuse box itself...what a mess. After 30 years the fuse clips get pretty loose in the box, push-on connectors get loose in their wires, and corrosion can be bad everywhere.

Swapped it out for a blade type fuse box (did nothing else) and it's been working great ever since.

First thing i did when i got the bike was to replace the old box with blade fuses. Going to check everything with the voltmeter, then may wire the ignition direct to the starter solenoid to see what occurs. Also going to clean all pertinent connectors.

2006hhr wrote:

...Also going to clean all pertinent connectors.

Good man!

K, looks pretty simple right? 1 wire from ignition to on/off on right control pod, splice to the starter switch, on to the coils and points/ pulse coils, so i have no power to the whole rack still. Might be a ground situation, will check that next. I know it should be a simple fix but electrical always mystifies me.

OK, i now have power all the way through the coils, but still no start? going to clean plugs and make sure everything is good there, connectors are all clean and good. Will keep everyone posted, wish me luck

Now how to check the coil voltage? I havepower going in, but seem to have nothing coming out, Dyna green 3 Ohm Coils by the way.

What did you fix to get power through to the coils? Pull the ground wire off a coil and read the ground coil terminal to ground with the ingition on. Should still see power. if not, there's a problem with the coil(s), but coils do not generally fail immdiately. If you do see power, then read the ground wire itself for continuity to ground (with it's related points closed). If that's good as well, pull a plug and lay it on the head still connected, then crank the engine to see if there is spark. If not, my guess would be a problem in the points area. Check connections and point gaps.