C0901

DTC C0901

Diagnostic Information

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

DTC Descriptor
DTC C0901
- Device 2 Voltage Low - EBCM

Diagnostic Fault Information





Circuit/System Description

The electronic brake control module (EBCM) monitors the ignition 1 voltage (IGN1) level available for system operation. A low voltage condition prevents the system from operating properly.

Conditions for Running the DTC

The ignition is ON.

Conditions for Setting the DTC

* Ignition 1 (IGN1) voltage to the EBCM is less than 6.5 volts for 7 seconds.
* Vehicle speed is greater than 3 km/h (2 mph).

Action Taken When the DTC Sets

The brake warning indicator turns ON.

Conditions for Clearing the DTC

* The DTC passes when the condition for the DTC is no longer present.
* The EBCM automatically clears a history DTC when a current DTC is not detected in 100 consecutive drive cycles.

Reference Information
Schematic Reference

Antilock Brake System Schematics ([1][2]Antilock Brakes / Traction Control Systems)
Connector End View Reference

Component Connector End Views (Connector 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 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 (Charging System Test) .

2. Observe the scan tool EBCM Battery Voltage parameter. The reading should be between 12.60 and 15.00 volts.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the EBCM.
2. Ignition OFF and scan tool disconnected, open and close the driver door, and wait 1 minute. Test for less than 5 ohms between the ground circuit terminals listed below and ground:

* Terminal 2
* Terminal 3

• 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 1
* Terminal 4

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

4. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal 21 and ground.

• 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.