C0901

DTC C0901

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 C0901
- Device 2 Voltage Low - EBCM




Diagnostic Fault Information






Typical Scan Tool Data






Circuit/System Description

The electronic brake control module (EBCM) monitors the ignition voltage level available on the VSES/ABS ignition 1 circuit for system operation. A low voltage condition prevents the system from operating properly.


Conditions for Running the DTC

Vehicle speed is greater than 3 km/h (2 mph).


Conditions for Setting the DTC

The ignition voltage to EBCM is less than 6.5 volts for 7 seconds.


Action Taken When the DTC Sets

* The antilock brake system (ABS), traction control system (TCS) and vehicle stability enhancement system (VSES) are disabled for the duration of the ignition cycle.
* The ABS and BRAKE indicators illuminates on the IPC.
* The DIC displays the BRAKES and ABS FAULT messages.



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.



Reference Information
Schematic Reference

Antilock Brake System Schematics (Electrical Diagrams)
Connector End View Reference

Component Connector End Views (Component Connector End Views)
Description and Operation

ABS Description and Operation (Description and Operation)
Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

Scan Tool Reference

Control Module References (Programming and Relearning) 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 (Component Tests and General Diagnostics) .

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



Circuit/System Testing

1. Ignition OFF, disconnect the harness connectors at the EBCM.
2. With the ignition OFF and the scan tool disconnected, open and close the drivers door, and wait 30 seconds. Test for less than 1.5 ohms between the ground circuit terminals listed below and ground:

* Terminal 4 X1
* Terminal 1 X2
* Terminal 32 X2


• 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 2 X1
* Terminal 2 X2
* Terminal 31 X2

4. Verify that a test lamp illuminates between the ignition circuit terminals listed below and ground:

* Terminal 1 X1
* Terminal 46 X2


• If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance.

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



Repair Instructions

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


Control Module References (Programming and Relearning) for EBCM replacement, setup, and programming