Circuit Description
Ground is continuously supplied to the low side of the ABS pump motor. The electronic brake control module (EBCM) activates the ABS pump by supplying adequate current to the high side of the motor.
Conditions for Running the DTC
| • | The ignition is ON. |
| • | The EBCM has commanded the pump motor ON at least once during the current ignition cycle. |
Conditions for Setting the DTC
The EBCM detects an open pump motor circuit, a shorted pump motor, or a seized pump motor or ABS pump.
Action Taken When the DTC Sets
| • | The EBCM disables the ABS. |
| • | The ABS indicator turns ON. |
| • | The ABS fault message is displayed. |
| • | An ECE 13 response occurs. Refer to ABS Description and Operation for a complete description of ECE 13. |
Conditions for Clearing the DTC
The Conditions for Setting the DTC are no longer present and you use the scan tool Clear DTCs function.
Diagnostic Aids
Separate the EBCM from the BPMV in order to inspect for corrosion or any other condition that may cause a poor connection at the pump motor connectors. Refer to Electronic Brake Control Module Replacement and Testing for Intermittent Conditions and Poor Connections . If severe corrosion or other damage exists, the BPMV or the EBCM may need to be replaced.
Inspect for poor connections that may affect the battery positive voltage circuit to terminal 4 or the ground circuit to terminal 3 of the EBCM harness connector if this DTC continues to set intermittently. Replace the EBCM if no wiring concerns are found.
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Antilock Brake System Schematics Connector End View Reference: Antilock Brake System Connector End Views | |||
1 | Did you perform the ABS Diagnostic System Check? | Go to Step 2 | |
2 |
Does the DTC reset? | Go to Step 3 | Go to Diagnostic Aids |
3 |
Does the test lamp illuminate? | Go to Step 5 | Go to Step 4 |
4 | Repair the open in the battery positive voltage circuit. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 12 | -- |
5 | Connect a test lamp between the battery positive voltage circuit at terminal 4 of the EBCM harness connector and the ground circuit at terminal 3 of the EBCM harness connector. Does the test lamp illuminate? | Go to Step 7 | Go to Step 6 |
6 | Repair the open in the motor ground circuit. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 12 | -- |
7 |
Did you find and correct the condition? | Go to Step 12 | Go to Step 8 |
8 |
Important: The test lamp must remain properly connected to the pump motor terminals whenever the ignition is ON, or incorrect test results may be obtained.
Does the test lamp illuminate and then turn OFF with each command? | Go to Step 9 | Go to Step 11 |
9 | Press the Exit key on the scan tool. Does the DTC reset? | Go to Step 11 | Go to Step 10 |
10 | Replace the BPMV. Refer to Brake Pressure Modulator Valve Replacement . Did you complete the replacement? | Go to Step 12 | -- |
11 | Replace the EBCM and the BPMV. Refer to Electronic Brake Control Module Replacement and Brake Pressure Modulator Valve Replacement . Did you complete the replacements? | Go to Step 12 | -- |
12 |
Does the DTC reset? | Go to Step 3 | System OK |
