Code No.C1242: G and Yaw Rate Sensor System (Abnormality of Longitudinal G Sensor Output Signal)


caution
  • 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.
  • 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 GROUP 35C - On-vehicle Service )

OPERATION



DIAGNOSIS CODE SET CONDITIONS




  • Abnormality in G and yaw rate sensor output value
  • This diagnosis code is set when AWC-ECU determines that an abnormality is present by comparing the longitudinal G that is output from the G and yaw rate sensor during braking with the calculation value calculated by the data from the wheel speed sensor.

PROBABLE CAUSES



  • Improper installation of G and yaw rate sensor
  • Malfunction of G and yaw rate sensor
  • Malfunction of wheel speed sensor
  • Malfunction of stop lamp switch
  • Malfunction of ASC-ECU
  • Malfunction of AWC-ECU

DIAGNOSIS PROCEDURE

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 diagnosis code No.C1242 set?
Go to Step 3.
This diagnosis is complete.

STEP 3. M.U.T.-III diagnosis code.
Check the ASC diagnosis code. (Refer to GROUP 35C - Troubleshooting ).

Q. Is the check result normal?
Perform the relevant troubleshooting.
Go to Step 4.

STEP 4. M.U.T.-III diagnosis code.
Check if the stop lamp switch-related, or wheel speed sensor-related diagnosis code is set.

Q. Is the diagnosis code set?
Perform the relevant troubleshooting.
Go to Step 5.

STEP 5. Check of G and yaw rate sensor installation status.
Check that the G and yaw rate sensor is installed correctly. (Refer to GROUP 35C - G and Yaw Rate Sensor ).

Q. Is the check result normal?
Go to Step 6.
Reinstall the G and yaw rate sensor correctly. Then go to Step 6.

STEP 6. M.U.T.-III data list.
Item No.31: Longitudinal G sensor (refer to ).

Q. Is the check result normal?
Go to Step 7.
Replace the G and yaw rate sensor. (Refer to GROUP 35C - G and Yaw Rate Sensor ). Then go to Step 8.

STEP 7. Check whether the diagnosis code is reset.

Q. Is diagnosis code No.C1242 set?
Replace the AWC-ECU. (Refer to ). Then go to Step 8.
Intermittent malfunction. (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).

STEP 8. Check whether the diagnosis code is reset.

Q. Is diagnosis code No.C1242 set?
Return to Step 1.
This diagnosis is complete.