GM Service Manual Online
For 1990-2009 cars only

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 00: Device Voltage High - EBCM

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

B+

C0899 00

C0899 00

--

--

Ground

--

C0899 00

--

--

Typical Scan Tool Data

Battery Voltage Signal - EBCM

Circuit

Short to Ground

Open

Short to Voltage

Operating Conditions: Ignition ON, Engine OFF.

Parameter Normal Value: 12.60 Volts.

B+

0.00 Volts*

0.00 Volts*

--

*The scan tool will not communicate with the EBCM if the battery voltage is less than 7 volts.

Circuit/System Description

The electronic brake control module (EBCM) monitors the battery positive (B+) voltage. If the voltage level is too high, damage may result in the system. When a high voltage condition is detected, DTC C0900 00 sets.

Conditions for Running the DTC

The ignition is ON.

Conditions for Setting the DTC

The EBCM detects that the battery voltage is greater than 18 volts.

Action Taken When the DTC Sets

    • The antilock brake system (ABS), electronic brake force distribution (EBD), traction control system (TCS), and vehicle stability enhancement system (VSES) are disabled.
    • The ABS, BRAKE, and vehicle dynamics caution (VDC) warning indicators turn ON.
    • The driver information center (DIC) displays the SERVICE ESC and SERVICE TRACTION messages.
    • The ABS pump motor turns ON if the voltage is greater than 28 volts.

Conditions for Clearing the DTC

    • The indicators and DIC messages will turn OFF when the condition for setting the DTC is no longer present.
    • The DTC will pass when the condition for setting the DTC is no longer present, and the ignition is cycled.
    • The EBCM clears a history DTC when the DTC does not fail in 100 consecutive ignition cycles.

Diagnostic Aids

    • This DTC could be set by overcharging with a battery charger or jump starting.
    • A high voltage DTC in multiple modules indicates a concern in the charging system.

Reference Information

Schematic Reference

Antilock Brake System Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

    •  ABS Description and Operation
    •  Charging System Description and Operation

Electrical Information Reference

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

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

  1. Engine running, accessories OFF, measure and record the battery voltage at the battery terminals. The voltage should be between 12.6 and 15.0 volts.
  2. If not within the specified range, refer to Charging System Test.
  3. Observe the scan tool EBCM Battery Voltage Signal parameter. The reading should be between 12.6 and 15.0 volts.
  4. If greater than the specified range, replace the EBCM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for EBCM replacement, setup and programming.