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 C0899: Device Voltage Low - EBCM

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

IGN I

C0899

C0899

--

--

Ground

--

C0899

--

--

Typical Scan Tool Data

Battery Voltage - EBCM

Circuit

Short to Ground

Open

Short to Voltage

Operating Conditions: Ignition ON

Parameter Normal Value: 12.6 V

IGN I

0.0 V*

0.0 V*

--

*The scan tool will not communicate with the EBCM if there is 0 V on the circuit.

Circuit/System Description

The electronic brake control module (EBCM) monitors the ignition voltage level available on the ignition 1 circuit fed by the VSES/ABS fuse 52. A low voltage condition prevents the system from operating properly. If the EBCM detects low voltage on the ignition 1 circuit, DTC C0899 will set.

Conditions for Running the DTC

    • The ignition is ON.
    • The vehicle speed is greater than 3 km/h (1.8 mph)

Conditions for Setting the DTC

One of the following conditions exists:

    • The EBCM detects that the ignition voltage is less than 9.5 V for 10 seconds.
    • All wheel speed sensor power supplies have low voltage for 1 minute.

Action Taken When the DTC Sets

    • The antilock brake system (ABS), traction control system (TCS) and vehicle stability enhancement system (VSES) are disabled.
    • The electronic brake force distribution (EBD) is disabled, if the ignition voltage is less than 8.5 V.
    • The ABS and traction indicators turn ON.
    • The BRAKE indicator turns ON, if the battery voltage is less than 8.5 V.
    • The driver information center (DIC) displays the ABS FAULT, BRAKES, FLUID, SERVICE STAB SYS, and TRACTION FAILED messages.

Conditions for Clearing the DTC

    • The DTC will pass when the ignition voltage is greater than 9.5 V for 0.22 second.
    • The EBCM automatically clears a history DTC when a current DTC is not detected in 100 consecutive ignition cycles.

Diagnostic Aids

    • A low voltage DTC in multiple modules indicates a concern in the charging system.
    • The warning indicators and DIC messages may turn ON without any DTCs set, if the EBCM detects that the battery voltage is less than 9.5 V, and the vehicle speed is less than 3 km/h (1.8 mph).

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 V.
  2. If not within the specified range, refer to Charging System Test.
  3. Observe the scan tool EBCM Battery Voltage parameter. The reading should be between 12.6 and 15.0 V.

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connectors at the EBCM.
  2. With the ignition OFF and the scan tool disconnected, open and close the driver door, and wait 30 seconds. Test for less than 5 Ω between the ground circuit terminals listed below and ground.
  3. • Terminal 4 X1
    • Terminal 1 X2
    • Terminal 32 X2
    If greater than the specified range, test the ground circuit for an open/high resistance.
  4. Verify that a test lamp illuminates between the B+ circuit terminals listed below and ground.
  5. • Terminal 2 X1
    • Terminal 2 X2
    • Terminal 31 X2
  6. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminals listed below and ground.
  7. • Terminal 1 X1
    • Terminal 46 X2
    If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance.
  8. If all circuits test normal, replace the EBCM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for EBCM replacement, setup, and programming.