Troubleshooting a CDI Ignition?

I have a 99 Kawasaki priarie 300 I bought as a basket case. It did crank and run, but I didn't have any thread lock when i put on the cam gear, and it spun. After repairing that, I went ahead and topped off the batt charge, and now no sparky. It's a true CDI setup, and I haven't been able to get any farther than "buy all three components and see which one works". Surely there's a better way?

I take it. it's a two-stroke, then? That means no advancer, probably?

Anyway, try to measure the voltage on the coil. There should be none until you turn the motor over. Then a very short burst of voltage will appear on the coil. If it does that, then it's more likely the coil. If it doesn't, then it can be the pickups or the igniter.

Also, make sure only one side of the coil is grounded. If the other side is grounded, then you have a short somewhere (that may also be the way the kill switch kills the ignition... by shorting the coil to ground.)

It's a four stroke single cylinder. No advancer. It has a "brain box" a coil, and I believe a hall effect sensor which collapses the field. I think the Ignition is controlled by supplying power to the ignition computer. I'll start with checking the coil, as you suggested.

Check the obvious such as Kill Switch connections and ignition switch connections.

More often than not, the faulty component is the trigger coil.

I recently fixed an LTR450 with no spark. It had 2 laps after a rebuild of the engine and quit. Broken wire in the left handlbar switch that you could not see until I took the switch apart

Are you sure it's actually a CDI and not just a transistorized ignition like on the KZ's, then?

I looked for some diagrams, but could only find ones for similar KZ 4-wheelers. They were not CDI.

If power goes directly to the coil from the kill switch, then it's most likely not CDI. The troubleshooting is different between transistorized ignition and CDI.

I'm getting nothing on the primary side of the coil as far as voltage goes.
The best I can tell, everything I find, Kaw parts, and info all say it's definitely a cdi. The original sales brochures say it's a cdi. Kaw parts lists as parts a cdi ignition module, a coil, and an exciter coil, but doesn't say where to find the exciter coil. I've looked all over and only see wires coming from the stator housing, and one of the harnesses has only two wires, so I'm thinking that's where it is.

But I can't find a wiring diagram or any troubleshooting info except to just throw parts at it. I guess I could just start with the cheapest first and hope it's not the expensive one, but surely there's a better way.

I unhooked the wire I suspect is for the exciter, and got open, even when cranking, and also no voltage when cranking. I didn't check millivolts, but I figured surely if it works off of field displacement it would at least give a volt or two? But without knowing if I'm even checking the right connector I hate to call it the exciter...

With the key on I do get battery voltage to the module, but I don't know where to go on that beyond that.

The cdi's used on Briggs were all mechanical and easy to trouble shoot, but this is one wholly different critter.

jjdwoodman wrote:

I'm getting nothing on the primary side of the coil as far as voltage goes.
The best I can tell, everything I find, Kaw parts, and info all say it's definitely a cdi. The original sales brochures say it's a cdi. Kaw parts lists as parts a cdi ignition module, a coil, and an exciter coil, but doesn't say where to find the exciter coil. I've looked all over and only see wires coming from the stator housing, and one of the harnesses has only two wires, so I'm thinking that's where it is.

But I can't find a wiring diagram or any troubleshooting info except to just throw parts at it. I guess I could just start with the cheapest first and hope it's not the expensive one, but surely there's a better way.

I unhooked the wire I suspect is for the exciter, and got open, even when cranking, and also no voltage when cranking. I didn't check millivolts, but I figured surely if it works off of field displacement it would at least give a volt or two? But without knowing if I'm even checking the right connector I hate to call it the exciter...

With the key on I do get battery voltage to the module, but I don't know where to go on that beyond that.

The cdi's used on Briggs were all mechanical and easy to trouble shoot, but this is one wholly different critter.

I have built and fixed CDI's. Anytime one of them blows, it typically takes out the SCR and usually the storge cap itself, There are two PNP transistors that form a pushpull converter that frequently screw the pooch if the unit fails, BTW, most CDI's fail when some dingo hangs a coil on them that is too low in primary impedance,