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C0900



DTC C0900
Circuit Description

The Electronic Brake Control Module (EBCM) monitors the voltage level available for system operation. 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 C0900 Device Voltage High

Conditions for Running the DTC
The vehicle speed is greater than 8 km/h (5 mph).

Conditions for Setting the DTC
The system voltage is greater than 17 volts for 0.72 seconds.

Action Taken When the DTC Sets
If equipped, the following actions occur:
^ The EBCM disables the Antilock Brake System (ABS)/Traction Control System (TCS)/Vehicle Stability Enhancement System (VSES) for the duration of the ignition cycle.
^ The DRP does not function optimally.
^ The ABS indicator turns ON.
^ The Traction Control and Active Handling indicator turns ON.
^ The Driver Information Center (DIC) displays the following messages:
- Service ABS
- Service Traction System
- Service Active Handling

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
A possible cause of this DTC is overcharging.

Test Description
The numbers below refer to the step numbers on the diagnostic table.
2. Use the scan tool in order to inspect the voltage to the EBCM.
3. Use the scan tool in order to inspect the voltage to the Body Control Module (BCM). A high voltage value in multiple modules indicates a concern in the charging system.
4. Verifies that the condition is still present.