C0900

DTC C0900

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor
DTC C0900
- Device Voltage High - EBCM

Diagnostic Fault Information






Typical Scan Tool Data






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 the EBCM turns OFF the system relay which removes battery voltage from the solenoid valves and pump motor, and DTC C0900 00 sets.

Conditions for Running the DTC

The ignition is ON.

Conditions for Setting the DTC

The system voltage is greater than 16 volts for 100 msec.

Action Taken When the DTC Sets

* The traction control system (TCS) and vehicle stability enhancement system (VSES) are disabled for the duration of the ignition cycle.
* The antilock brake system (ABS) is disabled if ignition voltage exceeds 19.5 volts.
* The traction control off indicator turns ON.
* The ABS indicator turns ON if voltage exceeds 19.5 volts.

Conditions for Clearing the DTC

* The DTC will pass when the condition for setting the DTC is no longer present.
* The EBCM automatically clears a history DTC when the DTC does not fail in 100 consecutive drive 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 [1][2]Antilock Brakes / Traction Control Systems
* Starting and Charging Schematics Electrical Diagrams

Connector End View Reference

Component Connector End Views
Description and Operation

Charging System Description and Operation Description and Operation
Electrical Information Reference

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

Scan Tool Reference

Control Module References Control Module References

Circuit/System Verification

1. Engine running, accessories OFF, measure and record the voltage at 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 Testing and Inspection.

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

• If greater than the specified range, replace the EBCM.

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.

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