Normal Operation and Fault Conditions

The ABS module uses an internal solid state switch to operate the hydraulic pump motor.

The ABS module tests the hydraulic pump motor by activating it for 30 milliseconds.

The ABS module monitors the voltage drop across the hydraulic pump motor while the pump motor is being activated. After 30 milliseconds have passed, the ABS module stops applying voltage to the pump motor and monitors the voltage the spinning hydraulic pump motor is generating and the voltage drop across the hydraulic pump motor solid state switch. If the monitored voltages are not within the specifications, the ABS module sets one or more DTCs.

PPT H ABS MODULE DTC FAULT TRIGGER CONDITIONS

DTC	Description	Fault Trigger Conditions
C0020:11	ABS Pump Motor Control: Circuit Short to Ground	Sets when the ABS module detects the voltage drop across the solid state switch is too high when the pump motor is activated. This can be due to a shorted switch, a shorted motor or a locked motor.
C0020:12	ABS Pump Motor Control: Circuit Short to Battery	Sets when the ABS module detects more than 0.93 volt for longer than 3 seconds from the pump motor once the pump motor has been deactivated.
C0020:13	ABS Pump Motor Control: Circuit Open	Sets when the ABS module detects the voltage supplied to the ABS module is less than 10 volts, if there is an open or high resistance on the ABS pump motor circuit between the ABS module and the HCU, or if the ABS module is faulted internally.
C0020:71	ABS Pump Motor Control: Actuator Stuck	Sets when the ABS module detects hydraulic pump motor is not rotating when it is commanded to run.