Inspection Procedure 8: ASC OFF light stays ON after the ignition switch turned to ON.
caution
If there is any problem in the CAN bus lines, an incorrect DTC may be set. Prior to this diagnosis, diagnose the CAN bus lines (Refer to GROUP 54C - CAN Bus Diagnostics Table ).
Whenever ECU is replaced, ensure that the CAN bus lines are normal.
OPERATION
ASC-ECU sends the illumination request signal of ASC OFF light to the combination meter through ETACS-ECU via CAN communication.
By the operation of ASC OFF switch, the ASC OFF light illuminates when the ASC function is stopped.
When the ASC OFF switch is pressed for 3 seconds or more, the ASC system turns OFF.
When the ASC OFF switch is pressed for 15 seconds or more, the ASC is kept in ON state and the system cannot be turned OFF until the ignition switch turned ON next time.
COMMENTS ON TROUBLE SYMPTOM
This may be caused by faults in the CAN bus line, ETACS-ECU, combination meter or ASC-ECU.
PROBABLE CAUSES
ETACS-ECU malfunction
Combination meter malfunction
ASC-ECU malfunction
DIAGNOSIS
STEP 1. Using scan tool (M.U.T.-IIISE) special function
Perform the following special function by the combination meter system, and check if the ABS warning light illuminates (Refer to GROUP 54A - Combination Meter/Special function table ).
Item No.9: Indicator (AUTO)
Is the check result normal?
Go to Step 2.
Replace the combination meter (Refer to GROUP 54A - Combination Meter ).
STEP 2. Using scan tool (M.U.T.-IIISE) data list
Check the ETACS-ECU system data list (Refer to GROUP 54A - ETACS-ECU/Data list reference table ).
Item No.104: A.S.C./TCL OFF switch
Is the check result normal?
Go to Step 3.
Refer to GROUP 54A - ETACS/Inspection Procedure 15 "The ASC OFF switch signal is not received." .
STEP 3. Retest the system.
Does ASC OFF light turn ON and OFF normally?
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/How to Cope with Intermittent Malfunctions ).
Replace the hydraulic unit (integrated with ASC-ECU) (Refer to ).