C0068

DTC C0068 Circuit Diagram:

CIRCUIT DESCRIPTION
The pump motor circuit is integral to the Electronic Brake Control Module (EBCM). The EBCM microprocessor energizes the relay within the EBCM to supply battery voltage to the high side of the pump motor. When pump motor activation is required, the EBCM microprocessor grounds the low side of the pump motor.

CONDITIONS FOR SETTING DTC
- Vehicle speed 8 mph or greater
- EBCM internal relay on
- Pump motor commanded on and then off
- High voltage from low side of pump motor for 100 ms when expected to be low.

ACTION TAKEN WHEN DTC IS SET
- ABS indicator lamp is turned ON
- ABS is disabled

NOTE: This DTC is an Ignition Latched DTC which indicates the above is true until the ignition is turned to OFF (even if the cause of the DTC is intermittent).

DIAGNOSTIC AIDS
DTC C0068 is usually caused by a seized pump motor, but also can be caused by shorted pump motor windings or by poor power/ground at the 2-way EBCM connector. The pump motor is integral with the Brake Pressure Modulator Valve (BPMV) assembly and cannot be separately serviced. The EBCM or BPMV must be replaced if these tests show the pump motor EBCM internal circuitry have failed.

Important: The J 39200 (or equivalent) test leads must be calibrated to zero prior to making any resistance measurements. Refer to the tool users manual.

DTC CHART TEST DESCRIPTION

DTC C0068 Diagnostic Chart:

NOTE: Number(s) below refer to number(s) on the diagnostic chart.

2. Inspect the EBCM 2-way harness connector for damage.
3. Checks the resistance of the EBCM ground circuit at the 2-way connector.