The EBCM relay supplies power to the solenoid valves and pump motor. The EBCM relay activates when the ignition is turned to the ON position. Power is available to the solenoid valves and pump motor through the relay via the battery positive voltage circuit. The EBCM relay remains engaged until the ignition switch is turned to the OFF position or until the EBCM detects a malfunction which requires the system to be disabled.
• | The pump motor is ON for at least 0.3 seconds. |
• | The EBCM relay is ON. |
The pump motor is stalled or turning slowly.
The following actions occur:
• | The EBCM disables the ABS for the duration of the ignition cycle. |
• | The ABS warning indicator turns ON. |
• | A malfunction DTC is stored. |
• | The condition for setting the DTC is no longer present and the scan tool Clear DTCs function is used. |
• | The EBCM automatically clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles. |
• | Possible causes for DTC C1243 to set are: |
- | The pump motor has high resistance. |
- | The pump motor is turning too slowly. |
- | An internal EBCM malfunction exists. |
• | The pump motor is an integral part of the BPMV and is not serviced separately. |
The numbers below refer to the step numbers on the diagnostic table.
This test verifies the operation of the pump motor.
This step tests the pump motor circuits of the BPMV for an open.
This step tests the pump motor and pump motor circuits by supplying power and ground.
Step | Action | Value(s) | Yes | No |
---|---|---|---|---|
1 | Did you perform the ABS Diagnostic System Check? | -- | Go to Step 2 | |
Does the pump motor turn ON and OFF with each command? | -- | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems | Go to Step 3 | |
Does the resistance measure less than the specified value? | 5 ohms | Go to Step 4 | Go to Step 6 | |
Does the motor run for either test? | -- | Go to Step 5 | Go to Step 6 | |
5 |
Does the DTC reset? | -- | Go to Step 7 | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems |
6 | Replace the BPMV. Refer to Brake Pressure Modulator Valve Replacement . Did you complete the repair? | -- | Go to Step 8 | -- |
7 | Replace the EBCM. Refer to Electronic Brake Control Module Replacement . Did you complete the repair? | -- | Go to Step 8 | -- |
8 |
Does the DTC reset? | -- | Go to Step 2 | System OK |