C0900

DTC C0900

Diagnostic Instructions

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

Conditions for Running the DTC

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 stability system off and traction control off indicators turn ON.
* The ABS indicator turns ON if voltage exceeds 19.5 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

* 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.

Circuit/System Verification

1. Measure and record the voltage at the battery terminals with the engine OFF, and again with the engine running. Verify that the battery voltage is 11-16 volts with the engine OFF and with the engine running.

^ If the battery voltage is not within the specified range, refer to Charging System Test. Charging System Test

2. Observe the scan tool Battery Voltage parameter in the EBCM data list. Verify that the scan tool displays a value that is within 2 volts of the battery voltage recorded in step 1.

^ If the scan tool parameter is not within the specified range, refer to Circuit/System Testing.

3. Refer to Diagnostic Aids.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector of the EBCM.
2. Ignition ON, test for 11-16 volts between the B+ and the ground circuits of the EBCM.

^ If not within the specified range, test the circuits for an open, high resistance, or a short, or refer to Charging System Test. Charging System Test

3. If all circuits test normal, replace the EBCM.

Repair Instructions

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