Hi all, I have a 2006 TRX-250EX. I bought it used and it's had this electrical issue since day one (probably should have passed over this one but that's moot at this point).


When I turn the key on, the lights (headlight or neutral light) don't come on. It's like the battery is dead. The starter button doesn't work either. The previous owner had wired a button to short the starter solenoid and that cranks the starter and the engine fires. Once running, the neutral light and headlight are now lit. Oddly though, revving the engine causes the lights to dim instead of brighten.


My theory is that there is a short somewhere in the DC side that is grounding out the 12V from the battery and preventing the lights from turning on and the starter from working. Then once running, the AC from the stator provides juice to the lights (maybe protected from ground by a diode somewhere?). I can't explain the dimming with RPM's other than perhaps it's over-driving the diode and again shorting the voltage from the stator???


I'd seen this similar symptoms show up temporarily on another quad once and someone said that it was a stuck solenoid. He used a screw driver to short the solenoid and reset it and the quad started operating normally. I've ordered a new solenoid for this quad but I'm wondering if anybody else has experienced similar symptoms on a bike/quad before and has any other ideas.


Thanks!

 

Does atv charge?

 

You have no connection between the regulator and battery, or the connection has a high resistance. This is usually because the main fuse has blown, but can be a broken wire or a bad earth. It is not a problem with the solenoid.

 

Yeah, solenoid didn't help. Main fuse was blown but I replaced it and it didn't cure the issue. Where is the regulator on a 250EX? Is it the round black finned component on the left side?


I really appreciate your input on this! I'd love to get it running right!

 

I'll dig around looking for bad wires but most of them are pretty obscured and wrapped up in the main harness. Would you think it's worthwhile to just by a new main harness?

 

OMG, you da MAN! I feel so stupid for not finding this sooner (I've owned the quad for over a year). I finally just sat down with the electrical schematic and a meter and within a couple of minutes it was very obvious that you were right, there was no connection between the hot 12V line at the regulator to the battery. A little digging and it was simply a plug that had come undone between the fuse and the main harness. Plug that in and the neutral light comes right on and the handlebar starter switch works again! First thing I did was remove that stupid switch which shorted the solenoid and throw it in the garbage! :-)