The pump motor relay is part of the electronic brake control module (EBCM). The EBCM turns ON and OFF the pump motor relay as deemed necessary to activate the pump motor.
This diagnostic procedure supports the following DTC:
DTC C1251 Pump Motor Performance
DTC C1251 can be set anytime the pump motor is actuated.
The EBCM detects a stuck pump motor.
• | The Antilock Brake System (ABS) is disabled. |
• | The ABS warning indicator turns ON. |
• | The vehicle stability control (VSC) is disabled, if equipped. |
• | The VSC warning indicator turns ON, if equipped. |
The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.
Thoroughly inspect the wiring and the connectors. An incomplete inspection of the wiring and the connectors may result in a misdiagnosis, causing a part replacement with the reappearance of the malfunction.
The following are possible causes of the malfunction:
• | An open or high resistance in the EBCM ground circuits |
• | An internal EBCM malfunction |
If an intermittent malfunction exists, refer to Testing for Intermittent Conditions and Poor Connections .
The number below refers to the step number on the diagnostic table.
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 Diagnostic System Check - Vehicle? | Go to Step 2 | |
Does the DTC reset? | Go to Step 3 | Go to Diagnostic Aids | |
3 | Test the electronic brake control module (EBCM) ground circuits for an open or high resistance. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | Go to Step 5 | Go to Step 4 |
4 | Replace the brake pressure modulator valve (BPMV). Refer to Brake Pressure Modulator Valve Assembly Replacement . Did you complete the replacement? | Go to Step 5 | -- |
5 |
Does the DTC reset? | Go to Step 2 | System OK |