Antilock Brake System
DTC C0460
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 C0460 42
- Steering Position Signal Initialization Not Accomplished
DTC C0460 71
- Steering Position Signal Internal Failure
DTC C0460 72
- Steering Position Signal Rolling Count Invalid
DTC C0460 4B
- Steering Position Signal Calibration Not Accomplished
DTC C0460 5A
- Steering Position Signal Not Plausible
Diagnostic Fault Information
Circuit/System Description
The electronic brake control module (EBCM) supplies ignition voltage circuit and a low reference circuit to both the steering angle sensor and the yaw/lateral accelerometer sensor. The EBCM receives serial data messages from both the steering angle sensor and the yaw/lateral accelerometer sensor. The steering angle sensor provides a serial data signal to the EBCM that represents the steering wheel degree of rotation. The EBCM utilizes this signal to calculate the driver intended driving direction.
The steering angle sensor is a relative sensor and requires a two stage initialization that happens at each ignition cycle. The first stage is accomplished when the steering wheel is moved a few degrees in either direction. The second stage of the initialization happens usually when the vehicle speed reaches 15-20 km/h (9-12 mph) and the vehicle is driven in a straight line. When initialization is complete, the scan tool VSES Failed parameter will change from Yes to No.
The EBCM will automatically adjust the steering angle when the vehicle is driven in a straight line, and is driven to compensate for a steering angle that is not zero. This steering angle can be adjusted up to 15° without setting a DTC. The scan tool Steering Wheel Position parameter value includes the automatic adjustment made by the EBCM.
Conditions for Running the DTC
* Ignition ON.
* Ignition voltage is greater than 10 V.
Conditions for Setting the DTC
C0460 42
* The steering angle sensor takes too long to accomplish the second stage of initialization.
* Not all of the tires are of the proper size or matching brand.
C0460 4B
The steering angle sensor may not be calibrated.
C0460 5A
* The steering angle sensor signal may not be plausible with the wheel speeds and the yaw/lateral accelerometer sensor.
* DTC Sub Code 20:
* The steering angle sensor learned offset is greater than 15°.
* The steering angle has exceeded the allowable limit greater than 720°. This value is not reported on the scan tool which is limited to 224°.
* DTC Sub Code 21 - Steering Angle Sensor Signal Not Plausible
* DTC Sub Code 22 - Steering Angle Sensor Clamp Fault
* DTC Sub Code 25 - Steering Angle Sensor Tolerance Check
* DTC Sub Code 2D - Steering Angle Sensor Failure Suspicion
C0460 71
Steering angle sensor has an internal failure.
C0460 72
The steering angle sensor signal rolling count may be invalid.
Action Taken When the DTC Sets
* Vehicle stability enhancement system (VSES) is disabled.
* A driver information center message and/or a warning indicator may be displayed.
Conditions for Clearing the DTC
* The condition for the DTC is no longer present.
* The EBCM clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles.
Diagnostic Aids
* Confirm that all tires are of the proper size and that all are matching brands. Check and adjust all tires to the stated cold air pressure as identified on the tire placard. If a mis-sized or non-matching brand tire is present, inform the customer that in order for the vehicle stability enhanced system to function normally, tires need to be a uniform size and rolling diameter.
* The car should not pull in either direction causing the steering wheel to be OFF center while driving in a straight line on a level surface.
* Improperly mounted or loose steering angle sensor.
* A chaffing point may be found on the steering angle harness approximately 101 mm (4 in) from the female side of the X203 inline harness connector.
* If the steering position sensor calibration does not complete, test the circuits for an open, high resistance, short to ground or short to voltage. If the circuit tests normal replace the steering angle sensor.
DTC C0460 42
* This DTC may set if the vehicle has tires with different rolling diameters or there is a failure with a wheel speed sensor. Taking a snapshot of the VSES data while driving the vehicle in a straight line at highway speeds is a good way to identify this condition. Wheel speeds should be within 1.6 km/h (1 mph) of each other.
* This DTC may set, in conjunction with DTC C0460 5A, if the steering angle is not reading 0° while driving the vehicle in a straight line. Perform the scan tool, Steering Pos. Sensor Calibration procedure.
Note: This condition may cause unwanted activations of the electronic stabilitrak control system.
* Verify the EBCM/VSES, Yaw Rate Sensor Input is 0.0° per second data for a stationary vehicle parked on a level surface. If greater than 2.0° per second or less than -2.0° per second may indicate a failure in the yaw/lateral accelerometer sensor.
DTC C0460 71
This DTC may set if the steering angle sensor has an internal failure and is often set in conjunction with the C0460 72. The steering angle may not update when the steering wheel is turned. If this condition is present replace the steering angle sensor.
DTC C0460 72
Note: A chaffing point may be found on the steering angle harness approximately 101 mm (4 in) from the female side of the X203 inline harness connector.
This DTC may set if a short or open circuit occurs after ignition ON. This condition may also set with one or all of the following DTCs: U1500, U2142, U2143, C0292 39.
DTC C0460 4B
* This DTC may set if a short or open circuit. If the condition is no longer present during the next ignition cycle, this DTC will be in history. This condition may also set one or all of the following DTCs: U1500, U2142, U2143, C0292 39.
* This DTC may set when a new steering angle sensor has been installed and not calibrated. Perform the scan tool, Steering Pos. Sensor Calibration procedure and verify the DTC clears.
Note: Identify which enhanced sub code is set with DTC C0460 5A. The DTC sub codes can be found in the scan tool Diagnostic Trouble Codes (DTC)/Additional DTC Information/Enhanced DTC Data.
DTC C0460 5A with Sub Code 20
* If the enhanced sub code is 20, then the EBCM has attempted to adjust the steering angle more than the 15° limit. This DTC cannot be cleared unless a steering position sensor calibration procedure is done first. By performing the calibration, a new reference point is set for the 15° of allowable adjustment. Test drive the vehicle to ensure that the scan tool Steering Wheel Position parameter reads 0° after the centering procedure is complete. Verify there are no steering wheel alignment concerns. The car should not pull in either direction causing the steering wheel to be OFF center while driving in a straight line on a level surface. If alignment is required, perform the alignment and perform the scan tool, Steering Pos. Sensor Calibration procedure.
Note: This condition may cause unwanted activations of the electronic stabilitrak control system.
The steering angle may appear to be properly centered and the scan tool Steering Wheel Position parameter reading 0° when driving straight and still be up to 15° off due to the automatic compensation by the EBCM as described above.
* This DTC may set when turning the steering wheel to the end of steering wheel travel, if the steering gear is not properly centered. To determine if the gear is centered, using a scan tool, observe the Steering Wheel Position by determining what the steering wheel angle is at the end of the steering wheel travel in each direction. This must be done after ignition but before the vehicle is driven.
* With FE1: Soft Ride Suspension - The steering gear should be +62° in one direction and -62° in the other direction. If the value is greater than ±82° or less than ±42° the vehicle should be aligned. Perform the scan tool, Steering Pos. Sensor Calibration procedure.
Note: This condition may cause unwanted activations of the electronic stabilitrak control system when driving in a circle with the steering wheel close to the travel limit.
* With FE3: Sport Suspension - The steering gear should be +110° in one direction and -110° in the other direction. If either value is greater than ±90° or ±130° the vehicle should be aligned. Perform the scan tool, Steering Pos. Sensor Calibration procedure.
DTC C0460 5A with Sub Codes 25 or 2D
Sub codes 25 or 2D may set when the steering angle sensor is not properly centered/calibrated. Perform the scan tool, Steering Pos. Sensor Calibration procedure.
Reference Information
Schematic Reference
Antilock Brake System Schematics (Electrical Diagrams)
Connector End View Reference
Component Connector End Views (Connector End Views By Name)
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. Ignition ON, verify that DTC C0035, C0040, C0045, or C0050 is not set in the EBCM.
• If any of the DTCs is set, refer to Diagnostic Trouble Code (DTC) List - Vehicle (Diagnostic Trouble Code (DTC) List - Vehicle).
2. Verify that DTC C0460 is not set in the PSCM.
• If DTC C0460 is set in the PSCM, refer to DTC C0460 (Power Steering).
3. With the scan tool perform the Steering Pos. Sensor Calibration. Refer to Steering Angle Sensor Centering (Procedures).
4. Clear DTC and operate the vehicle within the conditions for running the DTC. Verify the DTC does not reset.
• If the DTC resets, refer to Circuit/System Testing.
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at the EBCM.
2. Ignition ON, test for less than 1 V between the following circuit terminals listed below and ground:
* Low Reference circuit terminal 40
* Ignition voltage circuit terminal 5
* CAN Bus High Serial Data circuit terminal 18
* CAN Bus Low Serial Data circuit terminal 19
• If greater than the specified range, test the appropriate circuit for a short to voltage.
3. Ignition OFF, test for infinite resistance between the following circuit terminals listed below and ground:
* Low Reference circuit terminal 40
* Ignition voltage circuit terminal 5
* CAN Bus High Serial Data circuit terminal 18
* CAN Bus Low Serial Data circuit terminal 19
• If less than the specified value, test the appropriate circuit for a short to ground.
4. Ignition OFF, disconnect the harness connector at the steering angle sensor.
5. Test for less than 2 ohm between the following circuit terminals listed below:
* Low reference circuit terminal 40 at the EBCM harness connector and terminal 6 at the steering angle sensor harness connector
* Ignition voltage circuit terminal 5 at the EBCM harness connector and terminal 1 at the steering angle sensor harness connector
* CAN Bus High Serial Data circuit terminal 18 at the EBCM harness connector and terminal 3 at the steering angle sensor harness connector
* CAN Bus Low Serial Data circuit terminal 19 at the EBCM harness connector and terminal 4 at the steering angle sensor harness connector
• If greater than the specified value, test the appropriate circuit for an open/high resistance.
6. If all circuits test normal, replace the steering angle sensor. If the DTC resets, replace the EBCM.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the repair.
* Steering Angle Sensor Replacement (Removal and Replacement)
* Control Module References (Programming and Relearning)for EBCM replacement, programming and setup