B1488
DTC B1488
CIRCUIT DESCRIPTION
The generator battery control module controls the generator through the generator field control circuit. The signal is a 5-volt pulse width modulation (PWM) signal of 128 Hz with a duty cycle of 0-100 percent. Normal duty cycle is between 5-95 percent. If the generator field control circuit is in the 95-100 percent range or pulled high to battery positive voltage, then DTC B1488 will set.
DTC DESCRIPTOR
This diagnostic procedure supports the following DTC:
DTC B1488 Generator L-Terminal Circuit High
CONDITIONS FOR RUNNING THE DTC
- The ignition is in the Run position.
- The engine RPM is less than or equal to 0 RPM.
CONDITIONS FOR SETTING THE DTC
The generator field control circuit is 100 percent, shorted to battery voltage, for greater than 5 seconds.
ACTION TAKEN WHEN THE DTC SETS
The generator battery control module will request the driver information center (DIC) message of Charging System Fault and commands ON the Battery indicator.
CONDITIONS FOR CLEARING THE DTC
- The generator field control circuit is at 0 percent duty cycle.
- Clear the DTC with a scan tool.
DIAGNOSTIC AIDS
Recommended Action:
- Correct L-Term short high condition.
- Clear the codes.
- Cycle the ignition.
IMPORTANT: You must cycle the ignition after clearing the DTC to turn OFF the DIC message of Service Charging System.
If a fault condition persists, replace the module.
TEST
