Ladies and Gentleman,

I purchased a Coolster 3125R second hand a few years ago, as an avid ATV racer/rider I was so excited when my kids got old enough to start riding. This ATV had been ridden hard and put up wet a number of times by the previous owner, but as a fairly competent mechanic I wasn't worried about that. Initially I replaced the spark plug, battery, and carb and the ATV ran for a year without issue.

This year I've had a new issue that I am unable to figure out: When I turn the key on I have no electrical power anywhere, I was hesitant to blame a brake interlock as the N and R lights do not illuminate, nothing. With the key on I can jump across the starter solenoid and the ATV starts right up and runs without issue. This tells me the main components of the machine are good, I'm just missing something early in the startup sequence, any help would be greatly appreciated.

 

I don't know that model at all but on most Chinese quads the ignition system is totally independent of the battery system, so the fact it runs has nothing to do with how good or bad the battery system is. Most problems which cause a total loss of battery power are caused by a bad earth or the main wire from battery to ignition switch. Do lights and dash light up once you have started it? If so the problem is between battery and regulator, usually a short wire with the main fuse in it, or the negative battery lead. If there is still no power with engine running, the problem is between fuse and ignition switch including the switch itself, or a bad earth.

 

@merryman I am having a similar issue with my coolster 125. Have a look at the video below if you would. What direction would you direct me to? Thanks so much!

 

First off, re-connect that earth and see what happens.

Have you checked that main wire from battery to fuse, to regulator and ignition switch?
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If the lights work AC from alternator, the fact that they work would mean nothing, as the totally separate battery system isn't working. If lights are worked from battery this means the fault is beyond the ignition switch.

 

@merryman Thank you for the response. Much appreciated. Wanted to follow up. Please see video. Thanks again sir.

 

As I wrote before, do the lights work from alternator or battery? If from alternator, it would indicate your battery circuit is dead, so check that red wire for power, where it plugs into the ignition switch. There are two completely separate switches in that ignition switch, one earths the kill wire, the other switches live from battery and rectifier on and off. If you are getting power too the switch (red) are you getting power out? Which wire is power out? I don't know, won't be black/white as that is kill from CDI, won't be green as that is earth. I always check for power with a test lamp as you can get volts showing on a meter when there is no power to back that up.

 

@merryman Problem solved! 😁