Inspection Procedure 7: ASC OFF indicator lamp stays ON after the electric motor unit is started.








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 - 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 indicator lamp to the combination meter through CAN communication.
  • By the operation of ASC OFF switch, the ASC OFF indicator lamp 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 electric motor switch is turned to the "ON" position next time.

COMMENTS ON TROUBLE SYMPTOM
This may be caused by faults in the CAN bus line, EV-ECU, combination meter or ASC-ECU.

PROBABLE CAUSES

  • Damaged wiring harness and connectors
  • Malfunction of EV-ECU
  • Combination meter malfunction
  • ASC OFF switch malfunction
  • ASC-ECU malfunction

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnostics
Use M.U.T.-III to diagnose the CAN bus lines.

Q. Is the check result normal?
Go to Step 2.
Repair the CAN bus lines (Refer to GROUP 54C - CAN Bus Diagnostics Table ). Then go to Step 9.

STEP 2. M.U.T.-III diagnosis code
Use M.U.T.-III to check the diagnosis code for the ASC system (Refer to ).

Q. Is the diagnosis code set?
Carry out the diagnosis for the diagnosis code chart (Refer to ).
Go to Step 3.

STEP 3. ASC OFF switch check
Refer to .

Q. Is the check result normal?
Go to Step 4.
Replace ASC OFF switch (Refer to ). Then go to Step 9.

STEP 4. Connector check: C-106 EV-ECU connector, B-117 ASC OFF switch connector

Q. Is the check result normal?
Go to Step 5.
Repair the damaged connector.

STEP 5. Wiring harness check between C-106 EV-ECU connector terminal No. 17 and B-117 ASC OFF switch connector terminal No. 1

  • Check the signal circuit for short circuit.

Q. Is the check result normal?
Go to Step 6.
Repair the wiring harness between C-106 EV-ECU connector terminal No. 17 and B-117 ASC OFF switch connector terminal No. 1.

STEP 6. M.U.T.-III diagnosis code for other systems
Using M.U.T.-III, check that diagnosis code No. U1102 is set by the combination meter system.

Q. Is the diagnosis code set?
Diagnose the combination meter (Refer to GROUP 54A - Combination Meter/Diagnosis Code ). Then go to Step 9.
Go to Step 7.

STEP 7. M.U.T.-III diagnosis code for other systems
Using M.U.T.-III, check that diagnosis code No. U1108 is set by the EV-ECU system.

Q. Is the diagnosis code set?
Perform troubleshooting on EV-ECU (Refer to GROUP 54D - EV-ECU/Diagnosis Code ). Then go to Step 8.
Go to Step 8.

STEP 8. Retest the system.

Q. Does ASC OFF indicator lamp 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 ). Then go to Step 9.

STEP 9. Retest the system.

Q. Does ASC OFF indicator lamp turn ON and OFF normally?
This diagnosis is complete.
Return to Step 1.