Sometimes these things come from the factor with wires crossed in the harness. My Jetmoto 150 I had a wire crossed, that I fixed right when I was putting it together. Guy I bought it from told me to check it as some of them had the terminals mixed up at the factory etc.

It's proably something simple.

 

I appreciate that thought about the wiring, but where do I get a wiring schematic so I can tell if it is wired correctly. There was no documentation with the unit, when it arrived.

 

Im thinking the same thing...Just not sure what direction to send him in..

 

We got a member here, LynnEdwards...real sharp guy when it comes to electrical just about everything from what I can see.. Give him a day or 2 to read this thread and Im sure he will be a huge help..

 

There is a safety interlock on your quad that prevents the starter from being engaged unless the braks is applied. The reason for the interlock is to make sure the quad won't start up in gear and lurch into someone. Its the same thing as your car, where the starter won't turn unless you're in neutral or park.

The way the quad senses if the brake is applied is by using the brake switch. If you look at the brake pedal you see it pulls down on a switch through a spring. That switch is adjustable, and I suspect yours is *way* out of adjustment.

If your brake switch is like mine, when the switch plunger is fully retracted the switch is open (brake light is off). When you pull out the plunger the switch closes (brake light turns on, safety interlock satisfied). When you pull out the plunger even further (too far) the switch opens up again and the brake light goes off. I suspect your brake switch adjustment is too tight so that it is already pulled out a little when the brake lever is *not* pushed, and pulled out too far when the brake *is* pushed.

I have a 150cc GY6 powered quad, but it is not a Tao Tao. The wiring may be similar to yours. I didn't have a wiring diagram for mine either when I bought it. I traced the whole thing out. Here it is again:

 

The first thing to do is figure out what CDI is in your quad. Does this look like your CDI?



I'm assuming so, if not we'll have to back track a bit. Assuming this does look like your CDI the next step is to figure out whether it is DC powered or AC powered. Most quads out there are AC powered off the stator, but more and more new quads are powered off +12 volts DC. Unfortunately the CDI's for those two as pictured above look nearly identical.

To find out which you have unplug the CDI and look at the CDI connector going into the wiring harness. Turn on the ignition and measure the DC voltage at the "AC power" pin to ground. If you measure 12 volts DC whn the ignition switch is on, and measure 0 volts DC when the ignition switch is off, then you have a DC powered CDI.

Switch your meter over to measure AC volts. Measure the same pin to ground on an AC scale while cranking the starter over. If you measure AC voltage in the range of 50 to 80 volts AC while cranking the starter then you have an AC powered CDI. The wiring diagram for my 150cc quad I posted earlier has an AC powered CDI.

Fo the ignition system to work its got to have power. The other things it needs are:

1) It can't be killed (i.e. kill switches are all off)
2) It needs a trigger pulse to tell the CDI when to fire
3) The major components have to work (CDI, Coil, Plug, trigger pickup coil, etc). But you've changed all those, right?
4) The wiring has to be correct.

You said in an earlier post that you disconnected the kill switch wire. How did you do that? Where did you do that? I'm thinking ahead to the next step (#1 above). Here's another enlightening test:

With the CDI unplugged, and the ignition on and all kill switches off, measure the resistance in ohms on the kill switch wire in the CDI wiring harness connector to ground. You should read open (infinite ohms). If you read zero ohms (or really low ohms) then you've got kill switch problems.

While you're at it, measure the ignition trigger pulse pin resistance in ohms to ground. You should measure 150 ohms or so. Ignition off or on - doesn't matter.

Measure the ignition coil pin resistance to ground. It should read less than 2 ohms, but not zero ohms.

Measure the ground pin resistance to ground. It should read zero ohms.

Let's see if these tests turn up anything...

 

Turn on the headlight switch and crank the engine. Do your headlights light up dimly when you are cranking the starter motor? Or do they stay off?

Most quad headlights are powered off the battery/12 volts charging system. But recently there was this post:

http://forums.atvconnection.com/chin...ghts-idle.html

Note that the quad in the above post was a tao tao also. I don't know the answer yet. I'd concentrate on the "no spark" problem first.

 

Spliffy, I have one of these switches on my quad. Even though I should know better, this "pushing in til it goes click" has *got* me more times than I would like to admit.

Did you notice this post:

http://forums.atvconnection.com/chin...es-starts.html

They got had as well, and your post here was the key to solving it.

 

This is a fantastic website! You are all so helpful and supportive. I will try to locate a voltmeter and test all of the leads. Keep those suggestions coming. Thanks so much. Thanks for the schematic as well.

 

Spliffy, I think you are an angel. I bought 2 new 150cc Tao Tao ATVs for me and my grandson to have some fun on. One of them would not start and I spent 3 days (off and on) troubleshooting, all to no avail. Then I found this post of yours and once I pushed the kill switch in, it fired right up. I don't think the owners manual adequately described this anywhere. Thank you so much for your help.
Sincerely, George