C1449

DTC C1439 or C1445

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 Descriptors
DTC C1439
- Steering Angle Sensor Initialization Incomplete

DTC C1445
- Vehicle Driven with Steering Angle Sensor not Initialized

Circuit/System Description

The electronic brake control module (EBCM) monitors the steering wheel position sensor signal for vehicle stability control (VSC) system operation.

Conditions for Running the DTC

Ignition is in the ON position.

Conditions for Setting the DTC

C1439

After the steering angle sensor zero point calibration is cleared due to, for example, fluctuations in the power source, the steering angle sensor zero point calibration cannot be obtained for 60 seconds of continuous driving.

C1445

Steering angle sensor zero point calibration cannot be obtained when the vehicle is driven without a record of steering angle sensor zero point calibration at a speed of 35 km/h (22 mph) or more for 30 seconds or more without the brake pedal being depressed.

Action Taken When the DTC Sets

* The ABS warning indicator turns ON.
* The ABS is disabled.
* The vehicle stability control (VSC) warning indicator turns ON.
* The VSC is disabled.

Conditions for Clearing the DTC

The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.

Reference Information
Schematic Reference

Antilock Brake System Schematics (Electrical Diagrams)
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 (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)

Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information

Circuit/System Verification

1. Verify DTC U0073, U0123, U0124, or U0126 are not set.

• If DTC U0073, U0123, U0124, or U0126 is set, refer to Diagnostic Trouble Code (DTC) List - Vehicle (Diagnostic Trouble Code (DTC) List - Vehicle).

2. Verify no speed sensor, yaw rate sensor or deceleration DTCs are set.

• If any speed sensor, yaw rate sensor or deceleration DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle (Diagnostic Trouble Code (DTC) List - Vehicle) prior to diagnosing C1439 or C1445.

3. Using a scan tool, perform yaw rate sensor calibration.
4. Drive the vehicle at 35 km/h (22 mph) for 5 seconds and verify steering wheel is correctly centered.

• If steering wheel is not correctly centered, check for proper wheel alignment.

5. If steering wheel is correctly centered, replace the EBCM/BPMV.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the EBCM.
2. Test for less than 1 ohm between the following ground circuit terminals and ground.

* Terminal 1
* Terminal 13

• If greater than the specified range, test the ground circuit for an open/high resistance.

3. Verify a test lamp illuminates between the following B+ circuit terminals and ground.

* Terminal 12
* Terminal 24
* Terminal 34

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

4. If all circuit tests normal, replace the steering position sensor.

Repair Instructions

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

* Brake Pressure Modulator Valve Replacement (Service and Repair)
* Control Module References (Programming and Relearning) for EBCM replacement, setup, and programming