1999-2002 TRX400EX Fourtrax Service Manual, Page 238Get this manual
ELECTRIC STARTER From page 17-2
Checkthe starter relay voltage (page 17-10)
Abnormal
Faulty ignition switch Blownfuse Faulty engine stop switch Faulty starter switch Loose or poor connector contact Open circuit in wire harness
Check the starter relay switch operation (page 17-10)Starter motor turns slowly Weak battery Poorly connected battery cable Poorly connected starter motor cable Faulty starter motor Starter motor turns, but engine does notturn Faulty starter clutch (section 10)