AULT CODE SETTING CONDITION
Fault Code KOEO KOER Continuous Memory
P1246 HY1 HY1
1) KOER & Continuous Memory DTC P1246: Verify Generator Drive Function
This DTC is set when PCM detects voltage regulator temperature (calculated generator load frequency) falls below 6 percent. Possible causes are:
? Generator Circuit Open, Or Shorted To GND Or PWR
? Faulty Generator Drive Mechanism
? Faulty Generator/Regulator Assembly
? Faulty PCM
Check generator drive belt condition and tension. Start engine and verify generator is turning. Repair as necessary. See appropriate GENERATORS & REGULATORS article in STARTING & CHARGING
SYSTEMS. If no faults are found, go to next step.
2) Verify Generator Is EEC Controlled
Turn ignition switch to OFF position. Disconnect negative then positive battery cable. Disconnect generator connector. Measure resistance between BATT SENSE terminal and GEN COM terminal at generator
harness connector. See Fig. 128 Fig. 130 . If resistance is 950 1050 ohms, go to next step. If resistance is not 950 1050 ohms, replace generator/regulator assembly.
3) Check Battery Sense Voltage At Battery
Reconnect generator connector. Reconnect battery cables to battery. Using a DVOM, measure voltage between battery terminals. Note voltage measurement. Using a DVOM, measure voltage between negative
battery terminal and generator harness connector BATT SENSE terminal. If voltage is within .5 volt (plus or minus) of battery voltage measurement, go to next step. If voltage is not within .5 volt of battery voltage
measurement, repair BATT SENSE circuit as necessary.
4) Check Generator Failure Mode
Turn ignition switch to OFF position. Connect scan tool to Data Link Connector (DLC). Ensure all accessories are off. Using scan tool, access GFSF PID from PID/DATA MONITOR & RECORD menu. Start
engine and raise engine speed to 2000 RPM. Note GFSF PID value. Wiggle and bend wiring harness between generator and PCM. Fault is indicated by a change in GFSF PID value. If a fault is indicated, go to
next step. If no fault is indicated, check charging system and repair as necessary. See appropriate GENERATORS & REGULATORS article in STARTING & CHARGING SYSTEMS.
There is more to this to check this system out but I just can'tcopy it all. I'm sure you have checked the fuse at rear of engine compt.
Please consider a to help us answer more questions.
Wednesday, November 28th, 2012 AT 6:01 PM