Inspection Procedure 7: TCL/ASC does not operate.


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 (Refer to GROUP 54C, Trouble code diagnosis ).
  • Whenever ECU is replaced, ensure that the CAN bus lines are normal.
  • When the hydraulic unit (integrated with TCL/ASC-ECU) is replaced, always carry out the calibration of the steering wheel sensor, the G and yaw rate sensor and brake fluid pressure sensor (Refer to , and ).

COMMENTS ON TROUBLE SYMPTOM
In case of this trouble symptom, the TCL/ASC system operation may be disabled. Diagnosis code may be set by the TCL/ASC system using M.U.T.-III.

PROBABLE CAUSES

  • Low battery output
  • Wiring harness or connector failure of CAN bus line
  • TCL/ASC-ECU malfunction
  • Engine coding data problem

DIAGNOSIS PROCEDURE

STEP 1. Diagnosis code check
Use M.U.T.-III to check the diagnosis code for the TCL/ASC system. (Refer to .)

Q. Is the check result normal?
Go to Step 2.
Carry out the diagnosis for the diagnosis code. (Refer to .)

STEP 2. Engine ECU coding data check
Using M.U.T.-III, check if any abnormality is present to the coding data below which are stored in the engine-ECU. (Refer to GROUP 00 - How to perform variant coding .)
A.S.C.
    OK: Available

Q. Is the check result normal?
Go to Step 3.
Replace the engine ECU [Refer to GROUP 13A - Engine-ECU <134 or 3A9> or GROUP 13B - Engine-ECU, Engine-A-M/T-ECU <135 or 4A9> or Refer to GROUP 13C - Engine-ECU (4G1)]. Then go to Step 4 .

STEP 3. Hydraulic unit (integrated with TCL/ASC-ECU) check
Check that the brake tube is correctly mounted to the hydraulic unit (integrated with TCL/ASC-ECU). (Refer to .)

Q. Is the check result normal?
Replace the hydraulic unit (integrated with TCL/ASC-ECU).(Refer to .) Then go to Step 4.
Connect the brake tubes correctly, and repair or replace the external brake lines of the hydraulic unit (integrated with TCL/ASC-ECU).

STEP 4. Operation check

Q. Does TCL/ASC system operate normally?
This diagnosis is complete.
Check the brake system related components other than the TCL/ASC system.