Circuit Description
The electronic brake control module (EBCM) monitors the voltage level of the EBCM case. If the voltage level is too high, damage may result in the system. When the EBCM detects a high voltage condition, the EBCM turns OFF the system relay which removes battery voltage from the solenoid valves and pump motor.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC C0820 EBCM Case Voltage
DTC Symptom | DTC Symptom Descriptor |
|---|---|
07 | Voltage Above Threshold |
Conditions for Running the DTC
The ignition is ON.
Conditions for Setting the DTC
The case voltage is greater than 2 volts for 0.1 seconds.
Action Taken When the DTC Sets
If equipped, the following actions occur:
| • | The EBCM disables the Antilock Brake System (ABS)/adaptive cruise control (ACC)/Vehicle Stability Enhancement System (VSES) for the duration of the ignition cycle. |
| • | The dynamic rear proportion (DRP) and Traction Control System (TCS) are degraded. |
| • | The ABS indicator turns ON. |
| • | The Traction Control indicator turns ON. |
| • | The driver information center (DIC) displays the Service Stability System message. |
| • | The red brake warning indicator turns ON. |
Conditions for Clearing the DTC
| • | The condition for the DTC is no longer present and the DTC is cleared with a scan tool. |
| • | The EBCM automatically clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles. |
Diagnostic Aids
Possible causes of this DTC are the following conditions:
| • | Internal short in the pump motor. |
| • | External battery supply shorted to case. |
| • | Internal EBCM battery supply shorted to case. |
The pump motor is integral to the brake pressure modulator valve (BPMV). The pump motor is not serviceable.
Test Description
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 | |
2 |
Does the DTC reset? | Go to Step 3 | Go to Testing for Intermittent Conditions and Poor Connections |
Does the test lamp illuminate? | Go to Step 5 | Go to Step 4 | |
4 | Test both ground circuits of the EBCM including the EBCM ground for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | Go to Step 9 | Go to Step 6 |
5 | Inspect for poor connections at the pump motor harness pigtail connector of the BPMV. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | Go to Step 9 | Go to Step 7 |
6 | Inspect for poor connections at the harness connector of the EBCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | Go to Step 9 | Go to Step 8 |
7 | Replace the BPMV. Refer to Brake Pressure Modulator Valve Replacement . Did you complete the repair? | Go to Step 9 | -- |
8 | Replace the EBCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the repair? | Go to Step 9 | -- |
9 |
Does the DTC reset? | Go to Step 2 | System OK |
