1998-2001 Honda Fourtrax Foreman TRX450S, TRX450ES Factory Service Manual, Page 350Get this manual
IG NITION SYSTEM
TROUBLESHOOTING
Inspect the fo ll owing before diagnosing the system:Faulty spank plugLoose spark pluQi cap or spark ptug wire connectionWater got loto the spark cap (leaking the ignition call secondary voltage Temporarily exchange the ignition coil with another one and pertorm the spark testIf here is spark, he origlnal ignit ion call is faulty Before starti:ng' troubleshootingdisconnect thealterniitor 5P connectorand check continuity' between the Yellow (leM connector on the wir'e h8nless side} and Yellow on the wire namess side of the alternator oonnect'o rNo spark at plug Unusual condition Ig nition coil Low peak vo ltage
Pr,oDable cause (Check in numerical order)
1The multimater impedance :is too 2Cranking speed is too low3The sa mpling time of the tester and measured pulse were not synchronized (System is normal if measured vo ltage is over the standard vol;tage at least once), 4-Poor connection or ,a ll open circuit in ignition systems,Faulty ignition pul se generator (Measure the peak voltagel6Faulty ICM (Ifabove are normal)