Well, I was running the dunes in Glamis last weekend, having a blast and the Trail Boss just shut down. The engine shut down and all electircal was out except for the headlights. Nothing worked except for the Hi-low beams. No dash lights, break lights & the engine wouldn't turn over. My first thought was that the light for the whip shorted the electrical, but idea was shot down when the boss decided to come back to life! About 5 mins after the shutdown, the dash light came on- showed in Neutral (which I was). Then the boss turned over and started right up!

I'm wondering if the quad has a shutdown mode if the engine gets too hot? The funny thing is that the oil cooler fan did not kick on. I'm hoping that if the fan is not turning on, the oil heats up too much and the motor shuts down. Has anyone out there had this problem? I have the service manual, but it does not give a complete electrical breakdown of all the components...ANY IDEAS?

 

Not sure on the 03, but it sounds like for some reason the circuit breaker tripped, although I would expect the headlights to not work either - unless they are on a different circuit breaker (circuit breakers are in a black inline "pouch" near the battery)

 

I've seen similar things happen to Yamaha bikes. One had a faulty Stater, which when hot, stopped working. Another just simply shut off until it cooled, and I never did diagnose it.