U1427

DTC U1427: Wheel Speed 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.

OPERATION

AWC-ECU communicates with the ASC-ECU via the CAN bus lines.

DTC SET CONDITIONS

The code is set when abnormality is detected in the signal received from the wheel speed sensor.

PROBABLE CAUSES

- The CAN bus line is defective.
- Malfunction of ASC-ECU
- Malfunction of wheel speed sensor
- Malfunction of AWC-ECU

DIAGNOSTIC PROCEDURE

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. CAN Bus Diagnostics Chart).
STEP 2. Scan tool diagnostic trouble code

Check the ASC diagnostic trouble code. Active Stability Control System (ASC)).

Q. Is the DTC set?

YES Perform the relevant troubleshooting.
NO Go to Step 3.
STEP 3. Scan tool data list

Check the data list below. (Refer to Data List Reference Table).

- Item No.22: Wheel speed sensor [FL]
- Item No.23: Wheel speed sensor [FR]
- Item No.24: Wheel speed sensor [RL]
- Item No.25: Wheel speed sensor [RR]

Q. Is the check result normal?

YES Intermittent malfunction. How to Cope With Intermittent Malfunctions).
NO Go to Step 4.
STEP 4. Check whether the DTC is reset.

Q. Is DTC No. U1427 set?

YES Replace the AWC-ECU. (Refer to Twin Clutch-Sportronic Shift Transmission (TC-SST)). Then go to Step 5.
NO Intermittent malfunction. How to Cope With Intermittent Malfunctions).
STEP 5. Check whether the DTC is reset.

Q. Is DTC No. U1427 set?

YES Return to Step 1.
NO This diagnosis is complete.