Code No.C100A <FL>, C1015 <FR>, C1020 <RL>, C102B <RR>: Wheel Speed Sensor Circuit

  • If there is any problem in the CAN bus lines, an incorrect diagnosis 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.


4WD-ECU receives the wheel speed data from ABS/ASC-ECU via the CAN communication.


This diagnosis code is set when the abnormality below is detected:



STEP 1. M.U.T.-III CAN bus diagnostics.

Use M.U.T.-III to perform the CAN bus diagnosis.

Q. Is the check result normal?

Go to Step 3.
Repair the CAN bus lines (Refer to GROUP 54C - Troubleshooting ). After repairing the CAN bus line, go to Step 2.

STEP 2. Check whether the diagnosis code is reset.

Q. Is the relevant wheel speed sensor diagnosis code No.C100A <FL>, C1015 <FR>, C1020 <RL>, or C102B <RR> set?

Go to Step 3.
This diagnosis is complete.

STEP 3. M.U.T.-III other system diagnosis code.

Check the ABS diagnosis code (Refer to GROUP 35B - Troubleshooting ) <Vehicles with ABS> or the ASC diagnosis code (Refer to GROUP 35C - Troubleshooting ) <Vehicles with ASC>.

Q. Is the diagnosis code set?

Perform the relevant troubleshooting.
Go to Step 4.

STEP 4. M.U.T.-III data list.

Check the data list of the relevant wheel speed sensor (Refer to ).

  • Item No.18: FL wheel speed sensor
  • Item No.19: FR wheel speed sensor
  • Item No.20: RL wheel speed sensor
  • Item No.21: RR wheel speed sensor

Q. Is the check result normal?

Intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).
Replace the 4WD-ECU (Refer to ).