C0899
DTC C0899 or 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 C0899 00
- Device Voltage Low - EBCM
DTC C0900 00
- Device Voltage High - EBCM
Diagnostic Fault Information
Circuit/System Description
C0899
The electronic brake control module (EBCM) monitors the ignition voltage level available for system operation. A low voltage condition prevents the system from operating properly.
C0900
The EBCM monitors the ignition 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
C0899
This fault will be set if the ignition voltage to EBCM is less than 9 volts for 100 msec.
C0900
The system voltage is greater than 16 volts for 100 msec.
Action Taken When the DTC Sets
C0899, C0900
* The traction control system (TCS) and vehicle stability enhancement system (VSES) are disabled for the duration of the ignition cycle.
* The TCS indicator turns ON.
* The driver information center (DIC) displays the SERVICE STABILITRAK message.
C0900
* ABS disabled if ignition voltage exceeds 19.5 volts.
* The antilock brake system (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
* A high or low voltage DTC in multiple modules indicates a concern in the charging system.
* DTC C0900 could be set by overcharging with a battery charger or jump starting.
* Inspect the ground connection G115 to insure that it is clean and tight.
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 11-17 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 (Acadia or Enclave) Charging System Test (OUTLOOK). Charging System Test Charging System Test
2. Observe the scan tool Battery Voltage Signal 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 at the EBCM.
2. Test for less than 1.0 ohm between the ground circuit terminals 13 and 38, and the negative terminal of the battery.
• If greater than the specified value, test the ground circuit for an open/high resistance.
3. Ignition ON, verify that a test lamp illuminates between the B+ circuits of the EBCM terminals 1 and 25, and ground.
• If the test lamp does not illuminate, test the B+ circuits 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. Verification Tests