For 1990-2009 cars

### Diagnostic Instructions

• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

• | Review Strategy Based Diagnosis for an overview of this diagnostic approach.

• | Diagnostic Procedure Instructions provides an overview of each diagnostic category.

### DTC Descriptor

DTC C0899 00: Device Voltage Low - 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 voltage level available for system operation. A low voltage condition prevents the system from operating properly. If the EBCM detects low battery voltage, DTC C0899 00 will set.

### Conditions for Running the DTC

The ignition is ON.

### Conditions for Setting the DTC

One of the following conditions exists for 0.5 seconds, or 5 seconds if the engine is cranking:

• | The EBCM detects that the battery voltage is less than 9.7 volts, and the vehicle speed is greater than 0 km/h.

• | The EBCM detects that the battery voltage is less than 8.45 volts, regardless of vehicle speed.

### 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 battery voltage is less than 8.45 volts.

• | The ABS and vehicle dynamics caution (VDC) warning indicators turn ON.

• | The BRAKE warning indicator turns ON, if the battery voltage is less than 8.45 volts.

• | The driver information center (DIC) displays the SERVICE ESC, SERVICE TRACTION, and SVC BRAKE SYSTEM messages.

• | The DIC displays the ESC OFF message 1 time.

### 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

• | A low voltage DTC in multiple modules indicates a concern in the charging system.

• | The ABS, BRAKE, and VDC indicators and the DIC messages may turn ON without any DTCs set, if the EBCM detects that the battery voltage is less than 9.7 volts, and there is no vehicle speed.

### 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.

⇒ | If not within the specified range, refer to Charging System Test.

2. Observe the scan tool EBCM Battery Voltage Signal parameter. The reading should be between 12.6 and 15.0 volts.

### Circuit/System Testing

1. Ignition OFF. Disconnect the harness connector of the EBCM.
2. Ignition OFF and scan tool disconnected, open and close the driver door, and wait 1 minute. Test for less than 5 ohms between the ground circuit terminals listed below and ground:

• | Terminal 16 (JL4)

• | Terminal 26 (JM4)

⇒ | If greater than the specified range, test the ground circuit for an open/high resistance.

3. Verify that a test lamp illuminates between the B+ circuit terminals listed below and ground:

• | Terminal 1 (JL4/JM4)

• | Terminal 14 (JM4)

• | Terminal 32 (JL4)

⇒ | If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.

4. 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.