C0900

DTC C0900

DTC Descriptor
DTC C0900
- Device Voltage High

Diagnostic Fault Information

Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview






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 1 msec.

Action Taken When the DTC Sets

* ABS/EBD/Engine Traction System (ETS) disabled for the duration of the ignition cycle.
* ABS disabled if battery voltage exceeds 17 volts.
* The Antilock Brake System (ABS) indicator/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

* A possible cause of this DTC could be overcharging with a battery charger or jump starting.
* A high voltage value in multiple modules indicates a concern in the charging system.

Circuit/System Verification

1. If the DTC is history, refer to Charging System Test. Charging System Test
2. Start the engine, record the voltage at the battery terminals. Observe the battery voltage signal parameter in the EBCM data list. Voltages should not differ by more than 1 volt.

^ If more than 1 volt, replace the EBCM.

Repair Instructions

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

Control Module References for EBCM replacement, setup and programming.