2004 John Deer Buck Utility ATV 500, 500EX and 500EXT Service Manual, Page 41Get this manual
Go to next stepVerify condition of trigger coil and resistance with an ohmmeter and connector conditionDefective trigger coil andor corroded connector terminal? Replace trigger coilClean terminals and apply silicone dielectric greaseGo to next stepMechanically damaged part, vibration problem, electrically damaged part? Tighten mounting screw(s) andor replace magnetoGo to next stepMetallic particles caused short circuit between the soldered connections? Clean connector and trigger coil from metallic dustGo to next stepCheck magneto for damage andor electrical failureWindings of stator have electrical failure? Replace magnetoGo to next stepCheck electronic module for damage andor electrical failureElectronic module shows visual damage andor electrical failure? Replace electronic moduleRefer to "Diagnosing HydraulicMechanical Components", Problem With HydraulicMechanical Shift SystemSee "Diagnosing HydraulicMechanical Components" on page 42Go to next stepReplace fuseGo to next stepGo to step 5Go to step 5Electrical shift system is goodIs the shift shaft moving while depressing the shift button? Go to step 2Refer to "Diagnosing HydraulicMechanical Components", Problem With HydraulicMechanical Shift SystemSee "Diagnosing HydraulicMechanical Components" on page 42 Go to next stepGo to step 8