The electronic brake control module (EBCM) monitors the voltage level of the EBCMs 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.
This diagnostic procedure supports the following DTC:
DTC C0820 Device Ground Circuit
The ignition is ON.
The case voltage is greater than 2 volts for 0.1 seconds.
If equipped, the following actions occur:
• | The EBCM disables the ABS/ACC/VSES for the duration of the ignition cycle. |
• | The DRP and TCS are degraded. |
• | The ABS indicator turns ON. |
• | The Traction Control indicator turns ON. |
• | The DIC displays the Service Stability System message. |
• | The red Brake warning indicator turns ON. |
• | The condition for the DTC is no longer present and the DTC is cleared with a scan tool. |
• | The electronic brake control module (EBCM) automatically clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles. |
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 BPMV. The pump motor is not serviceable.
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 |
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 replacement? | Go to Step 9 | -- |
8 | Replace the EBCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | Go to Step 9 | -- |
9 |
Does the DTC reset? | Go to Step 2 | System OK |