My son has A 2002 325 Trail Boss , yesterday the heat light came on and the fan started running on high (assuming this has a 2 speed fan) , I unplugged the temp sensor thinking this should stop the fan but it didn`t . unplugged 2 yellow wires nothing changed not sure what the blue wire does , orange wire killed the fan and temp light and red wire slowed fan down when unplugged . Would this mean the the module is gone and where can I get one everwhere I try says they are backordered . I took the sensor out and put heat to it and got resistance reading so I think it is ok.
Kent

 

Sounds like something a thermistor module would do. If they get real hot you can usually see a bulge in the plastic case or it will be melted in the back. Don't know the availability here.Dirt Cheap Yamaha, Honda, Arctic Cat & Polaris OEM Parts & Accessories – Cycle Parts Warehouse