1999-2004 Honda TRX400EX FourTrax Service Manual, Page 232Get this manual
IGNITION SYSTEM
IGNITION PULSE GENERATOR PEAK VOLTAGE
NOTE Check that the cylinder compression is normal and the spark plug is installed correctly in the cylinder headDisconnect the ignition control module (ICM) 4P connectorConnect the peak voltage tester or adaptor probes to the connector terminals of the wire harness side
CONNECTION: Bluelyellow I+) Greenlwhite (4 Turn the ignition switch ONCrank the engine with the starter motor and read the peak voltage
PEAK VOLTAGE 0.7 minimum
If the voltage measured at ICM connector is abnormal, measure the peak voltage at the alternator connectorRemove the seatlrear fender (page 2-2)Disconnect the alternator 4P connector and connect the peak voltage tester or adaptor probes the bluelyellow and green wire terminals of the alternator side connectorIn the same manner as at the ICM connector, measure the peak voltage and compare it to the voltage measured at the ICM connector-