I wasn't sure where to place this, but I had a similar problem.

I have an AC CDI, checked my CDI and coil on another machine and it runs fine.

My issue is that the AC ignition pin gets no voltage or resistance to the ground pin. However, if I unplug the 4 pin connector (only 3 used pins) from the engine harness and hook one of the leads to the ground pin on the engine harness and the other lead to the ignition pin on the CDI harness, I do get the proper voltage (about 35-40 Vac). Same with the timing pulse, it gets no voltage when I crank it when the leads are connected at the CDI harness, but if I connect the ground lead to the ground pin on the engine harness, I get voltage.

That means my stator is working properly, right? Do I have some sort of ground problem between the engine harness and the cdi harness? Where would I start looking?

Incidentally there is a red plug and white plug that have only two pins that mate together. They each have a yellow wire and a grey(green? I'm color blind) wire, but it is setup so that each yellow wire meets with the oposing grey/green wire, rather than colors matching,the way the rest of the harness is. Is that strange?

As far as the test numbers go:

Connected to CDI plug pin
1) shows 1. (2k ohms scale)
2) Shows 1, looks like it is open (2k ohms scale)
3) 2 ohms (2k ohms scale)
4) 0 volts (200 AC)
5) says .1 volts with it on 200 AC, but that is what this cheapo thing flickers between when it isn't cranking
6) not much activity, flickers between .1 and .3, .8 etc.

With ground lead connected to engine side pin
1) shows 1.
2) Shows 1 too (??)
3) Shows 1 too
4) bounces around, 40, 25, 25 volts
5) on 200 AC (my lowest setting), it shows like 35 volts???
6) on 200 AC, it bounces around 35, 55, 40, sometimes higher, etc.

 

Lynn is the electrical expert here and hopefully he will see this and be able to help you out. I am still way green when it comes to these chinese atvs but I am learning more about them.

 

But the stator ignition power stuff should always be measured with the CDI unplugged. So I'm confused that you measure the AC ignition power wire voltage and then unplug the 4 pin connector to measure it again. Both CDI connectors (4 and 2 pin) should always be disconnected when you measure this. So when you say you get voltage only after you unplug one of two connectors I wondering why we are on this path.


What do these wires hook to? If they are just a connector set with both wires disappearing into the wiring harness then look everywhere on the quad and find the same color wires at other connectors. A grey/green wire (for example) that enters the wiring harness will still be the same color (and almost certainly the same wire) when it re-emerges somewhere else. What do those same color wires connect to? That will give a clue as to what these wire's function are, and whether or not it is important.


I'm confused about the above tests. These are supposed to be done with the CDI disconnected (except for test 6). But from from your earlier results I wondering if they are...

Please redo the tests again (CDI unplugged for tests 1-5), but this time do it two ways:

1) Do all the tests as outlined (using the ground pin on the CDI harness connector).
2) Do all the tests, only this time using an engine ground as the ground reference - the black lead on the meter (instead of the ground pin on the CDI connector).

Also switch to ohms on the 200 ohms scale and measure the resistance of the ground pin on the CDI harness connector to engine ground (you should get zero ohms).

On your second set of measuements I'm even more confused. You connected the "ground lead" to "engine side pin".

A) What ground lead? At the CDI connector? Elsewhere?
B) What is an "engine side pin"?

Often times certain words mean different things to different people. What may seem perfectly clear to one person makes no sense to another. I'm just trying to shed some light on an uncertain scenario.

 

Sorry, I wasn't clear, the CDI WAS unplugged for the tests. What I mean is I unplugged the CDI harness from the main harness and tested directly at the main harness, to see if there was a problem with the wiring from the main harness to the CDI plugs.

Let me look at the rest of your reply and answer separately.

 

RE Engine side pin, I mean the ground pin on the main harness that the ground pin on the CDI plug ostensibly connects to. I unplugged the 4 pin plug at the main harness, which is what I think the CDI part of the harness plugs into, no?

I will try to do these tests again tonight. When you say "engine ground" do you just mean the engine case or the frame? Or a certain connection or somehting?

Sorry for all of the confusing terminology.

 

Also, could you remind me which color wire is supposed to be plugged into the coil terminals? I have a black and green terminal on the coil, and there is a green (ground?) wire and a black and yellow (trigger pulse?) wire. I assume that the green goes to the black and the black and yellow goes to the green, but maybe other way around?

 

I may have figured out what was wrong, and you won't believe it:

I have not wanted to pull the flywheel cover off because I know I don't have the tool to remove the flywheel. But I decided to do it today and found some pretty interesting stuff:

First, the nut holding the flywheel on was hand tight (???). so I zipped it off and then felt the flywheel to see if it was tight. It jiggled, which I thought was odd enough. So I fiddled with it and it popped off. But guess what came with it? The stator! There were no bolts holding the stator down! Like none, not even snapped off or laying in with the magnet. Just not there. And the stator was slightly chewed up on the side facing the flywheel. So I am pretty sure this is probably what is wrong with the machine. On a hunch, and because it was cheap, I ordered in a stator and it is at the post office waiting for me to pick it up. Will have to stop at the hardware store to look for some bolts to hold the stator down too. . . .

I got this machine for $250 bucks, I think someone played around with this before, since I highly doubt the flywheel and stator came like this from the factory. The college kid I bought it from said he drove it to school, parked it and went to class and it wouldn't start afterwards. Either he lied to me, he tried to fix it himself and didn't inform me, or someone tore apart his bike in the parking lot and swappped out their bad stator for his good one (highly unlikely, but since the local scooter shop is asking $95 for the stator and they charge about $150 to change them, I can see why someone might do that).

Still trying to figure out the coil wire though.

 

I think that sounds right.

 

I see now. When I read "engine side pin" I didn't read "engine side" pin. I read engine "side pin". I was wondering what a "side pin" was, and where it would be on the engine... .

Yes, Engine ground would is the engine case or the frame.

 

I would bet the kid had someone else look at, who took it apart and then gave up for what ever reason. Then it just got thrown back together - probably with the intention of trying again later. Then the kid needed money and decided to sell. He may or may not not have known it was in such a loose assembled state.