Inspection Procedure 5: AS&G System Abnormal (auto stop not carried out) <4N1>


caution If the following services are performed, the backup data should be deleted. Do not perform these services without carrying out the check described in Step 2.

  • In case the cable is disconnected from the battery terminal
  • In case the connector is disconnected from the engine-ECU

FUNCTION



COMMENTS ON TROUBLE SYMPTOM



  • The failure could possibly be caused by the failed AS&G system. The AS&G-ECU, however, can possibly prohibit the auto stop, depending on the vehicle status or the ambient conditions.

PROBABLE CAUSES



  • Deteriorated battery
  • Failed AS&G system
  • Short circuit in starter active signal circuit, or loose connector contact
  • Failed AS&G-ECU

DIAGNOSIS PROCEDURE

STEP 1. Confirm the vehicle status and the ambient conditions.

  • Confirm the vehicle status or the ambient conditions to check whether the auto stop should be carried out or not (Refer to ).

Q. Are the conditions for prohibiting the auto stop satisfied?
Check end.
Go to Step 2.

STEP 2. M.U.T.-III data list

  • Check the data lists of the engine-ECU (Refer to GROUP 13B - Troubleshooting - Data List Reference Table ).
  • Item 435: Last battery deteriorated odometer
  • Item 436: 2nd last battery deteriorated odometer
  • Item 437: 3rd last battery deteriorated odometer
OK: 0 km (Ignition switch: ON)

Q. Are the all items displayed as "0 km"?
Go to Step 3.

    Write the check result and go to Step 3.

STEP 3. M.U.T.-III diagnosis code
Confirm the diagnosis code is set from the following ECU.

  • AS&G-ECU
  • Engine-ECU
  • ASC-ECU
  • Combination meter
  • EPS-ECU
  • A/C-ECU
  • ETACS-ECU

Q. Is the diagnosis code set?
YES <Diagnosis code is set from the AS&G-ECU> : Perform the troubleshooting of the AS&G-ECU (Refer to ).
YES <Diagnosis code is set from the engine-ECU> : Perform the troubleshooting of the engine-ECU (Refer to GROUP 13B - Troubleshooting - Inspection Chart for Diagnosis Code ).
YES <Diagnosis code is set from the ASC-ECU> : Perform the troubleshooting of the ASC-ECU (Refer to GROUP 35C - Diagnosis Code Chart ).
YES <Diagnosis code is set from the combination meter> : Perform the troubleshooting of the combination meter (Refer to GROUP 54A - Combination Meter - Diagnosis Code Chart ).
YES <Diagnosis code is set from the EPS-ECU> : Perform the troubleshooting of the EPS-ECU (Refer to GROUP 37 - Diagnosis Code Chart ).
YES <Diagnosis code is set from the A/C-ECU> : Perform the troubleshooting of the A/C-ECU (Refer to GROUP 55 - Troubleshooting - Diagnosis Code Chart ).
YES <Diagnosis code is set from the ETACS-ECU> : Perform the troubleshooting of the ETACS-ECU (Refer to GROUP 54A - ETACS - Diagnosis Code Chart ).
Go to Step 4.

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

  • Item 10: Seat belt fasten status
OK:
    Fastened (Driver’s seat belt: Fastened)
    Not fastened (Driver’s seat belt: Not fastened)
note If the driver’s seat belt is unfastened, the AS&G indicator/display in the combination meter should blink.

Q. Is the check result normal?
Go to Step 5.
Perform the troubleshooting of the seat belt reminder function circuit (Refer to GROUP 54A - Combination Meter - Symptom Procedures - Seat Belt Reminder Function Does Not Work Normally ).

STEP 5. M.U.T.-III data list

  • Item 4: Engine hood
OK:
    Close (Hood: Closed)
    Open (Hood: Opened)
note If the engine hood is opened, the AS&G indicator/display in the combination meter should blink.

Q. Is the check result normal?
Go to Step 6.
Perform the troubleshooting of the engine hood latch switch circuit (Refer to GROUP 54A - ETACS - Input Signal Procedures - The hood latch switch signal is not received ).

STEP 6. M.U.T.-III data list

  • Refer to Data List Reference Table .

  1. Item 6: Clutch monitoring switch (upper)
  2. Item 7: Clutch interlock switch (bottom)
  3. Item 8: Neutral position switch
  4. Item 14: Brake vacuum sensor
  5. Item 16: Atmospheric pressure

Q. Are the check results normal?
Go to Step 7.
Perform the troubleshooting for the item that has an abnormal value (Refer to ).

STEP 7. M.U.T.-III data list

  • Refer to Data List Reference Table .

  1. Item 18: Accelerator pedal position

Q. Is the check result normal?
Go to Step 8.
Perform the troubleshooting of the accelerator pedal position sensor (Refer to GROUP 13B - Troubleshooting - Inspection Chart for Diagnosis Code ).

STEP 8. M.U.T.-III data list



  • Refer to Data List Reference Table .

  1. Item 17: Vehicle speed

Q. Is the check result normal?
Go to Step 9.
Perform the troubleshooting of the ASC-ECU (Refer to GROUP 35C - Troubleshooting - Diagnosis Code Chart ).

STEP 9. M.U.T.-III data list

  • Item 15: Ambient temperature
OK: At ambient temperature (atmospheric temperature) or equivalent

Q. Is the check result normal?
Go to Step 10.
Perform the troubleshooting of the ambient temperature sensor (Refer to GROUP 55 - Troubleshooting - Diagnosis Code Procedures - Ambient Temperature Sensor System ).

STEP 10. M.U.T.-III data list

  • Check the data lists of the engine-ECU (Refer to GROUP 13B - Troubleshooting - Data List Reference Table ).
  • Item 7: Engine coolant temperature sensor
OK:
    Engine cold state: At ambient temperature (atmospheric temperature) or equivalent.
    Engine hot state: At 80 - 120°C

Q. Is the check result normal?
Go to Step 11.
Perform the troubleshooting of the engine coolant temperature sensor (Refer to GROUP 13B - Troubleshooting - Inspection Chart for Diagnosis Code ).

STEP 11. Make certain the check result.
note If the situation falls under any of the following items, go to "YES" whether or not the check result in Step 2.

  1. After a malfunction occurs, the negative (-) cable is disconnected from the battery once.
  2. After a malfunction occurs, the connector is disconnected from the engine-ECU once.
  3. The odometer shown on the combination meter is beyond 262,140 km.

Q. Is the check result in Step 2 other than "0 km"?
Go to Step 12.
Go to Step 15.

STEP 12. M.U.T.-III data list

  1. Disconnect the negative (-) cable from the battery (this can delete backup data).
  2. Charge the battery (Refer to GROUP 54A - Battery - On-vehicle Service - Charging ).
  3. As soon as the battery is charged, leave the engine idling and turn off lamps and all accessories.
  4. Check the data lists of the engine-ECU (Refer to GROUP 13B - Troubleshooting - Data List Reference Table ).

  • Item No. 455: Battery full-charge mode flag
OK: The display status "ON" is changed to "OFF" within approximately 10 minutes.

Q. Is the check result normal?
Turn the ignition switch to "ON" position after stopping the engine. Then go to Step 14.

    Go to Step 13.

STEP 13. M.U.T.-III data list

  1. Turn the ignition switch to "ON" position (But do not start the engine).
  2. Check the data lists of the engine-ECU (Refer to GROUP 13B - Troubleshooting - Data List Reference Table ).

  • Item No. 434: Vehicle Consumption Current
OK:
  • When the headlamp is lit, the numerical value should increase by approximately 9 A. <Vehicles with halogen type headlamp>
  • When the headlamp is lit, the numerical value should increase by approximately 6 A. <Vehicles with discharge type headlamp>

Q. Is the check result normal?
Replace the battery.
Replace the battery current sensor.

STEP 14. Judge the battery life.

    1. Turn the ignition switch to "ON" position (But do not start the engine).
    2. Check the data lists of the engine-ECU (Refer to GROUP 13B - Troubleshooting - Data List Reference Table ) and adjust the electrical load so that the displayed value should be 30 ± 2 A.

    • Item No. 434: Vehicle Consumption Current
    3. Continue the conditions of Step 2 for 120 seconds and discharge the battery.
    4. Run the engine for 10 seconds after the engine start and check on the battery deterioration with data lists of the engine-ECU.

    • Item No. 454: Battery degrade judgment flag
OK: OFF (Engine: Idle operation)

    5. After checking that the data list item No. 454 of the engine-ECU is displayed, swiftly turn the ignition switch to "LOCK" (OFF) position and leave it for 10 seconds.
    6. Repeat Steps 1-5 five times. Check that data list item No. 454 always shows "OFF".

Q. Is the check result normal?
Recharge the battery because the battery is discharged during the check. (Refer to GROUP 54A - Battery - On-vehicle Service - Charging ). After the battery is charged, go to Step 16.
Replace the battery.

STEP 15. M.U.T.-III data list

  • Item 12: Idle stop enable (A/C-ECU)
  • Item 13: Idle stop enable (engine-ECU)
OK: "Enable" is displayed

Q. Is the check result normal?
Go to Step 16.
NO <"Disable" is displayed in item 12.> : The A/C-ECU would possibly output the auto stop prohibition signal. Recheck the auto stop prohibition signal of the A/C-ECU (Refer to GROUP 55 - General Information ).
NO <"Disable" is displayed in item 13.> : The engine-ECU would possibly output the auto stop prohibition signal. Recheck the auto stop prohibition signal of the engine-ECU (Refer to GROUP 13B - General Information ).

STEP 16. Connector check: B-09 engine-ECU connector and A-31X starter relay connector

Q. Are the check results normal?
Go to Step 17.
Repair or replace the connector.

STEP 17. Check harness between A-31X (terminal No. 3) starter relay connector and B-09 (terminal No. 8) engine-ECU connector.
note Before checking harness, check intermediate connector A-16 and repair if necessary.

  • Check output line for short circuit.

Q. Is the check result normal?
Go to Step 18.
Repair the damaged harness wire.

STEP 18. Check the trouble symptom.

Q. Does the trouble symptom persist?
Replace the AS&G-ECU.
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).