Inspection Procedure 2: Starting Impossible (starter not operative)


OPERATION



  • The ignition switch-ST signal is inputted into the AS&G-ECU (terminal No. 31) from the ETACS-ECU (C-403 ETACS-ECU connector terminal No. 15).
  • The battery voltage is supplied to the starter cut relay (terminal No. 4) from the battery.
  • The AS&G-ECU (terminal No. 25) turns ON the power transistor in the unit, and then makes the current flow into the starter cut relay terminal No. 2) to turn ON the relay.
  • When the starter cut relay is turned ON, the battery voltage is supplied to the starter relay (terminal No. 4) from the starter cut relay (terminal No. 3).
  • The AS&G-ECU (terminal No. 23) turns ON the power transistor in the unit, and then make the current flow into the starter relay (terminal No. 2) to turn ON the relay.
  • When the starter cut relay and starter relay are turned ON, the battery voltage is supplied to the starter (B-112 starter connector terminal No. 1) from the starter relay (terminal No. 3).
  • The starter cut relay (terminal No. 1) and the starter relay (terminal No. 1) are earthed to the vehicle body.

COMMENTS ON TROUBLE SYMPTOM



  • The failure could possibly be caused by the malfunction of the starter or starter system circuits. If the engine-ECU or the OSS-ECU stores the diagnosis code, the engine start should be restricted.

PROBABLE CAUSES



  • Failed battery
  • Failed clutch interlock switch
  • Open/short circuit or harness damage in clutch interlock switch circuit, or loose connector contact
  • Failed starter cut relay
  • Failed starter relay
  • Failed starter motor
  • Open/short circuit or harness damage in ignition switch-ST circuit, or loose connector contact
  • Open/short circuit or harness damage in starter cut relay circuit, or loose connector contact
  • Open/short circuit or harness damage in starter relay circuit, or loose connector contact
  • Failed ETACS-ECU
  • Failed AS&G-ECU

DIAGNOSIS PROCEDURE

STEP 1. Check battery

  • Check battery (Refer to GROUP 54A - Battery - On-vehicle Service - Battery Test ).

Q. Is the check result normal?
Go to Step 2.
Replace the battery.

STEP 2. M.U.T.-III diagnosis code

  • Confirm the diagnosis code is set from the engine-ECU.

Q. Is the diagnosis code set?
Perform the troubleshooting of the engine-ECU (Refer to GROUP 13B - Troubleshooting - Inspection Chart for Diagnosis Code <4N1>, Refer to GROUP 13D - Troubleshooting - Inspection Chart for Diagnosis Code <4A9>).
NO <Vehicles without OSS> : Go to Step 4.
NO <Vehicles with OSS> : Go to Step 3.

STEP 3. M.U.T.-III diagnosis code

  • Confirm the diagnosis code is set from the OSS-ECU.

Q. Is the diagnosis code set?
Perform the troubleshooting of the OSS-ECU (Refer to GROUP 42B - Troubleshooting - Diagnosis Code Chart ).
Go to Step 4.

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

  • Item 7: Clutch interlock switch
OK:
    ON (Clutch pedal: Fully depressed)
    OFF (Clutch pedal: Released)

Q. Is the check result normal?
Go to Step 5.
Perform the troubleshooting of diagnosis code No. P0833: Clutch interlock switch circuit (Refer to ).

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

  • Item 1: Starter switch
  • Clutch pedal: Fully depressed
OK:
    ON (Ignition switch: ST)
    OFF (Ignition switch: ON)

Q. Is the check result normal?
Go to Step 16.
Go to Step 6.

STEP 6. Perform voltage measurement at C-415 ETACS-ECU connector by back probing.

  • Do not disconnect connector.
  • Clutch pedal: Fully depressed
  • Ignition switch: ST
  • Voltage between terminal No. 7 and earth.
OK: System voltage

Q. Is the check result normal?
Go to Step 11.
NO <Vehicles without OSS> : Go to Step 7.
NO <Vehicles with OSS> : Go to Step 9.

STEP 7. Connector check: C-309 ignition switch connector and C-415 ETACS-ECU connector

Q. Are the check results normal?
Go to Step 8.
Repair or replace the connector.

STEP 8. Check ignition switch itself.

  • Check ignition switch itself (Refer to GROUP 54A - Ignition Switch - Inspection - Ignition Switch Check ).

Q. Is the check result normal?

    Check and repair harness between C-309 (terminal No. 5) ignition switch connector and C-415 (terminal No. 7) ETACS-ECU connector.

    • Check signal line for open/short circuit and damage.
Replace the ignition switch.

STEP 9. Connector check: C-14 OSS-ECU connector and C-415 ETACS-ECU connector

Q. Is the check result normal?
Go to Step 10.
Repair or replace the connector.

STEP 10. Check harness between C-14 (terminal No. 23) OSS-ECU connector and C-415 (terminal No. 7) ETACS-ECU connector.

  • Check signal line for open/short circuit and damage.

Q. Is the check result normal?
Perform the troubleshooting of the OSS-ECU (Refer to GROUP 42B - Troubleshooting <OSS-ECU> - Symptom Chart ).
Repair the damaged harness wire.

STEP 11. Connector check: C-403 and C-415 ETACS-ECU connectors, C-11 AS&G-ECU connector, B-10 <4N1> or B-27 <4A9> engine-ECU connector

Q. Are the check results normal?
Go to Step 12.
Repair or replace the connector.

STEP 12. Continuity check on C-403 and C-415 ETACS-ECU connectors.

  • Disconnect connectors, and check at ETACS-ECU side.
  • Continuity check between terminal No. 7 (C-415) and terminal No. 15 (C-403).
OK: Continuity

Q. Is the check result normal?
Go to Step 13.
Replace the ETACS-ECU.

STEP 13. Check harness between C-403 (terminal No. 15) ETACS-ECU connector and C-11 (terminal No. 31) AS&G-ECU connector.

  • Check signal line for open/short circuit and damage.

Q. Is the check result normal?
Go to Step 14.
Repair the damaged harness wire.

STEP 14. Check harness between C-403 (terminal No. 15) ETACS-ECU connector and B-10 (terminal No. 111) <4N1> or B-27 (terminal No. 105) <4A9> engine-ECU connector.



  • Check signal line for short circuit.

Q. Is the check result normal?
Go to Step 15.
Repair the damaged harness wire.

STEP 15. 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 ).

STEP 16. Connector check: A-22X starter cut relay 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 the starter cut relay itself and starter relay itself.

  • Check the starter cut relay itself and starter relay itself (Refer to GROUP 16 - Starting System - On-vehicle Service - Starter Relay Continuity Check ).

Q. Are the check results normal?
Go to Step 18.
Replace the starter cut relay and/or starter relay.

STEP 18. Perform resistance measurement at A-22X starter cut relay connector.

  • Remove the relay, and measure at harness side.
  • Resistance between terminal No. 1 and earth.
OK: Continuity (2 Ω or less)

Q. Is the check result normal?
Go to Step 19.

    Check and repair harness between A-22X (terminal No. 1) starter cut relay connector and body earth.

    • Check earthing line for open circuit and damage.

STEP 19. Perform resistance measurement at A-31X starter relay connector.

  • Remove the relay, and measure at harness side.
  • Resistance between terminal No. 1 and earth.
OK: Continuity (2 Ω or less)

Q. Is the check result normal?
Go to Step 20.

    Check and repair harness between A-31X (terminal No. 1) starter relay connector and body earth.

    • Check earthing line for open circuit and damage.

STEP 20. Check harness between battery and A-22X (terminal No. 4) starter cut relay connector.

  • Check power supply line for open/short circuit and damage.

Q. Is the check result normal?
Go to Step 21.
Repair the damaged harness wire.

STEP 21. Connector check: C-11 AS&G-ECU connector

Q. Is the check result normal?
Go to Step 22.
Repair or replace the connector.

STEP 22. Check harness between C-11 (terminal No. 25) AS&G-ECU connector and A-22X (terminal No. 2) starter cut relay connector.

  • Check signal line for open/short circuit and damage.

Q. Is the check result normal?
Go to Step 23.
Repair the damaged harness wire.

STEP 23. Check harness between A-22X (terminal No. 3) starter cut relay connector and A-31X (terminal No. 4) starter relay connector.

  • Check output line for open/short circuit and damage.

Q. Is the check result normal?
Go to Step 24.
Repair the damaged harness wire.

STEP 24. Check harness between C-11 (terminal No. 23) AS&G-ECU connector and A-31X (terminal No. 2) starter relay connector.

  • Check signal line for open/short circuit and damage.

Q. Is the check result normal?
YES <4N1> : Go to Step 25.
YES <4A9> : Go to Step 27.
Repair the damaged harness wire.

STEP 25. Connector check: B-09 engine-ECU connector

Q. Is the check result normal?
Go to Step 26.
Repair or replace the connector.

STEP 26. 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 open/short circuit and damage.

Q. Is the check result normal?
Go to Step 27.
Repair the damaged harness wire.

STEP 27. Connector check: B-112 and B-113 starter connector

Q. Are the check results normal?
Go to Step 28.
Repair or replace the connector.

STEP 28. Check harness between A-31X (terminal No. 3) starter relay connector and B-112 (terminal No. 1) starter connector.
note Before checking harness, check intermediate connector B-108 <4N1>, A-17 <4A9> and repair if necessary.

  • Check output line for open/short circuit and damage.

Q. Is the check result normal?
YES <4N1> : Go to Step 31.
YES <4A9> : Go to Step 29.
Repair the damaged harness wire.

STEP 29. Connector check: B-26 engine-ECU connector

Q. Is the check result normal?
Go to Step 30.
Repair or replace the connector.

STEP 30. Check harness between B-112 (terminal No. 1) starter connector and B-26 (terminal No. 6) engine-ECU connector.

  • Check output line for short circuit.

Q. Is the check result normal?
Go to Step 31.
Repair the damaged harness wire.

STEP 31. Check harness between battery and B-113 (terminal No. 1) starter connector.

  • Check power supply line for open/short circuit and damage.

Q. Is the check result normal?
Go to Step 32.
Repair the damaged harness wire.

STEP 32. Check starter motor operation.

  • Check starter motor operation (Refer to GROUP 16 - Starting System - Starter Motor Assembly - Starter Motor Assembly Inspection <4N1>, <4A9>).

Q. Is the check result normal?
Go to Step 15.
Replace the starter motor.