Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
DTC Descriptors
DTC C012D 00: Brake Boost Regulation Pressure SensorDTC C128D: Brake Boost Regulation Pressure Sensor
DTC C012D 01: Brake Boost Regulation Pressure Sensor Short to Battery
DTC C12BD: Brake Boost Regulation Pressure Sensor Short to Battery
DTC C012D 06: Brake Boost Regulation Pressure Sensor Short to Ground or Open
DTC C12BC: Brake Boost Regulation Pressure Sensor Short to Ground or Open
DTC C012D 11: Brake Boost Regulation Pressure Sensor Above Maximum Threshold
DTC C128A: Brake Boost Regulation Pressure Sensor Above Maximum Threshold
DTC C012D 5A: Brake Boost Regulation Pressure Sensor Plausibility Failure
DTC C120A: Brake Boost Regulation Pressure Sensor Plausibility Failure
DTC C012D 0F: Brake Boost Regulation Pressure Sensor Erratic
DTC C12BE: Brake Boost Regulation Pressure Sensor Erratic
Circuit/System Description
The electronic brake control module (EBCM) uses input from the boost pressure sensor for more accurate control during brake and vehicle stability enhancement system (VSES) event. The boost pressure sensor is internal to the brake pressure modulator valve (BPMV).
Conditions for Running the DTC
| • | Ignition ON. |
| • | The ignition voltage is greater than 10 volts. |
Conditions for Setting the DTC
C012D 00, C128D, C012A 11 or C128A
Internal sensor failure is detected.
C012D 01 or C12BD
A short to battery is detected on the sensor signal circuit.
C012D 06 or C12BC
A short to ground or open is detected signal circuit.
C012D 5A or C120A
The boost pressure being commanded is not being achieved.
C012D OF or C12BE
Signal is erratic and changes faster than physically allowed.
Action Taken When the DTC Sets
| • | The EBCM disables the ABS and vehicle stability enhancement system (VSES) for the duration of the ignition cycle. |
| • | A DIC message and/or a warning indicator may be displayed. |
Conditions for Clearing the DTC
| • | The condition for setting the DTC is no longer present. |
| • | The EBCM clears the history DTC when a current DTC is not detected in 40 consecutive drive cycles. |
Reference Information
Schematic Reference
Antilock Brake System Schematics
Connector End View Reference
Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
Verify that DTC C012D, C120A, C128A, C128D, C12BC, C12BD, or C12BE is not set.
| ⇒ | If DTC is set replace EBCM/brake pressure modulator valve (BPMV) assembly. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for EBCM replacement, setup, and programming |
