Circuit Description
Steering angle centering is the process which calibrates the steer sensor output so that it reads 0 when the steering wheel is centered, using data from the yaw rate sensor, lateral accelerometer and wheel speeds. Under normal circumstances steer angle centering occurs after approximately 10 seconds of driving in a straight line on a fairly level surface (i.e. a typical road) at > 10 KPH.
The usable output voltage range for the lateral accelerometer and yaw rate sensors is 0.25-4.75 volts. The scan tool will report zero lateral acceleration or yaw rate as 2.5 volts with no sensor bias present. The sensor bias compensates for sensor mounting alignment errors, electronic signal errors, temperature changes, and manufacturing differences.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC C0253 Centering Error
Conditions for Running the DTC
The vehicle speed is greater than 40 km/h (25 mph).
Conditions for Setting the DTC
The vehicle has been driven for 10 minutes without completing steer angle centering.
Action Taken When the DTC Sets
| • | The EBCM disables the VSES for the duration of the ignition cycle. |
| • | The DIC displays the Service Stability System message. |
| • | The ABS/TCS remains functional. |
Conditions for Clearing the DTC
| • | The condition for the DTC is no longer present and the DTC is cleared with a scan tool. |
| • | The EBCM automatically clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles. |
Diagnostic Aids
The following conditions can cause this concern:
| • | Improper steering alignment. |
| • | Open, short to ground, or short to voltage. |
| • | Internal lateral accelerometer failure. |
| • | EBCM internal failure. |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
Verify that the condition is current.
-
Verify that the Lateral Accelerometer Signal parameter is within the valid range.
-
Verify that the Yaw Rate Sensor parameter is within the valid range.
Step | Action | Values | Yes | No |
|---|---|---|---|---|
Schematic Reference: Antilock Brake System Schematics Connector End View Reference: Antilock Brake System Connector End Views | ||||
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | |
Operate the vehicle under the conditions for running the DTC. Does DTC C0253 reset? | -- | Go to Step 3 | Go to Diagnostic Aids | |
With a scan tool, observe the Lateral Accelerometer Signal parameter in the VSES data list. Does the scan tool display within the specified range? | 2.3-2.7 V | Go to Step 4 | Go to Step 8 | |
With a scan tool, observe the Yaw Rate Sensor parameter in the VSES data list. Does the scan tool display within the specified range? | 2.3-2.7 V | Go to Step 5 | Go to Step 8 | |
5 |
Does DTC C0253 reset? | -- | Go to Step 6 | Go to Diagnostic Aids |
6 | Replace the electronic brake control module (EBCM). Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | -- | Go to Step 9 | -- |
7 | Replace the SWPS. Refer to Steering Wheel Position Sensor or Steering Shaft Lower Bearing Replacement . Did you complete the replacement? | -- | Go to Step 9 | -- |
8 | Replace the yaw rate/lateral accelerometer sensor. Refer to Vehicle Yaw Sensor with Vehicle Lateral Accelerometer Replacement . Did you complete the replacement? | -- | Go to Step 9 | -- |
9 |
Does DTC C0253 reset? | -- | Go to Step 2 | System OK |
