GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Opel 🢒 2007 🢒 GT 🢒 Brakes 🢒 Antilock Brake System 🢒 DTC C0900

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 Descriptor

DTC C0900: Device Voltage High

Circuit/System Description

The electronic brake control module (EBCM) monitors the battery voltage. If the voltage level is too high, damage may result in the system. When a high voltage condition is detected the EBCM turns OFF the system relay which removes battery voltage from the solenoid valves and pump motor.

Conditions for Running the DTC

Ignition is ON.

Conditions for Setting the DTC

The system voltage is greater than 17 volts for 10 msec.

Action Taken When the DTC Sets
    • ABS disabled if ignition voltage exceeds 17 volts.
    • The Antilock Brake System (ABS) indicator and engine traction (ETS)/ brake warning lamp turns ON if voltage exceeds 17 volts.

Conditions for Clearing the DTC
    • The condition for the DTC is no longer present.
    • The EBCM automatically clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles.

Diagnostic Aids

Test the charging system. Refer to Battery Inspection/Test and Charging System Test .

Reference Information

Schematic Reference

Antilock Brake System Schematics

Connector End View Reference

Antilock Brake System Connector End Views

Description and Operation

ABS Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Scan Tool Data List for EBCM

Circuit/System Testing
  1. Measure the voltage at the battery terminals.
  2. With scan tool, read the battery voltage in the EBCM data list.
    3. ⇒If more than 17 volt, test the check the charging system.
  3. Go to Battery Inspection/Test and Charging System Test .

Repair Instructions

Perform the Diagnostic Repair Verification After completing the diagnostic procedure.

    •  Control Module References for EBCM replacement, setup, and programming
    •  Generator Replacement