U1428

DTC U1428: G and Yaw Rate Sensor Data Error

CAUTION
^ If there is any problem in the CAN bus lines, an incorrect diagnostic trouble code may be set. Prior to this diagnosis, diagnose the CAN bus lines.
^ Whenever the ECU is replaced, ensure that the CAN bus lines are normal.
^ Do not drop the G and yaw rate sensor or subject it to a shock.
^ When G and yaw rate sensor is replaced, calibrate G and yaw rate sensor (refer to On-vehicle Service Removal and Replacement)

OPERATION
AWC-ECU receives the G and yaw rate sensor data from ASC-ECU via the CAN communication.

DTC SET CONDITIONS
The code is set when abnormality is detected in the signal received from the G and yaw rate sensor.

PROBABLE CAUSES
^ Malfunction of G and yaw rate sensor
^ Malfunction of ASC-ECU
^ Malfunction of AWC-ECU

DIAGNOSIS

STEP 1. Scan tool CAN bus diagnostics
Using scan tool MB991958, diagnose the CAN bus lines.
Q: Is the check result normal?
YES: Go to Step 2.
NO: Repair the CAN bus lines. (Refer to Troubleshooting CAN Bus Diagnostics Table).

STEP 2. Scan tool diagnostic trouble code
Check the ASC diagnostic trouble code. (Refer to Troubleshooting Diagnostic Trouble Code Descriptions).
Q: Is the DTC set?
YES: Perform the relevant troubleshooting.
NO: Go to Step 3.

STEP 3. Scan tool diagnostic trouble code
Check if the ACD diagnostic trouble code No. C123C, C1242 is set. (Refer to Diagnostic Trouble Code Descriptions).
Q: Is the check result normal?
YES: Perform the relevant troubleshooting.
NO: Go to Step 4.

STEP 4. Scan tool data list
Check the data list below. (Refer to Data List Reference Table).
^ Item No. 26: Yaw rate sensor
^ Item No. 29: Lateral G sensor
^ Item No. 31: Longitudinal G sensor
Q: Is the check result normal?
YES: Go to Step 5.
NO: Replace the G and yaw rate sensor. Then go to Step 6.

STEP 5. Check whether the DTC is reset.
Q: Is DTC No.U1428 set?
YES: Replace the AWC-ECU. Then go to Step 6.
NO: Intermittent malfunction. (Refer to How to Cope with Intermittent Malfunction How to Use Troubleshooting/Inspection Service Points).

STEP 6. Check whether the DTC is reset.
Q: Is DTC No.U1428 set?
YES: Return to Step 1.
NO: This diagnosis is complete.