Code C1242

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This code is for the ABS control module. The powers and grounds need to be verified before assuming the module is bad.
Below is the description and steps needed to check for the failure.

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Circuit Description:
The system relay is energized when the ignition is ON. The system relay supplies voltage to the solenoid valves and the pump motor. This voltage is referred to as the system voltage. The EBCM controls each solenoid valve by grounding the solenoid. The EBCM controls the pump motor by grounding the control circuit. The pump serves 2 purposes:
Transfers brake fluid from the brake calipers to the master cylinder reservoir during pressure decrease events.
Transfers brake fluid from the master cylinder reservoir to the brake calipers during pressure increase events.

Conditions for Running the DTC

C1242
The system voltage is greater than 8.0 volts.
The system relay is ON.
The pump motor is commanded OFF.

C1243
The pump motor is ON for at least 0.3 seconds.
The system relay is ON.

Conditions for Setting the DTC

C1242
The voltage across the pump motor is between 1.7-10.2 volts for 2 seconds.

C1243
The pump motor is stalled or turning slowly.

Action Taken When the DTC Sets
If equipped, the following actions occur:
The EBCM disables the ABS/TCSNSES for the duration of the ignition cycle.
The DRP does not function optimally.
The ABS indicator turns ON.
The Traction Control indicator turns ON.
The DIC displays the Service Stability System message.

Conditions for Clearing the DTC
The condition for the DTC is no longer present (the DTC is not current) and you used the scan tool Clear DTC function.
The condition for the DTC is no longer present (the DTC is not current) and you used the On-Board Diagnostics Clear DTC function.
The EBCM automatically clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles.

Diagnostic Aids
The pump motor is integral to the BPMV. The pump motor is not serviceable.

Test Description
The number below refers to the step number on the diagnostic table.
3. Tests the ability of the EBCM to control the pump motor. If the test lamp illuminates, the pump motor circuit within the EBCM is good.