2006-2009 Honda TRX250EX/TRX250X Service Manual, Page 333Get this manual
IGNITION SYSTEM Remove the CKP sensor 2P green connector from the frame and disconnect it
Connect the tester probes to th Bluelyellow wire terminal (+1and Green wire terminal of the alternator side connector In the same manner as at the ICM connector, measure the peak voltage and compare it to the voltage measured at the ICM connector If the peak voltage measured at the ICM is abnormal and the one measured at the CKP sensor is normal, the wire harness has an open circui or loose connection If both peak voltages are abnormal, check each item in the troubleshooting cha rt on page 18-4If all items are normal, the CKP sensor is faultyAlternator stator replacement (page 1161
ALTERNATOR EXCITER COil PEAK VOLTAGE
NOTE: Check that the cylinder compression is normal and the spark plug is installed correctly in the cylinder head