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Home >> Toyota >> 2009 >> Corolla XRS, Automatic >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 13 (Engine Control System (2ZR-FE) - System And Component Testing, On-Vehicle Inspection, Removal & Installation) >> ECM Power Source Circuit >> Inspection Procedure
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Inspection Procedure

WARNING: This page is about a different variant/trim than selected.
  1. CHECK HARNESS AND CONNECTOR (ECM - BODY GROUND) 
    1. Disconnect the ECM connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Condition
      B31-104(E1) - Body ground Always Below 1 Ω
    3. Reconnect the ECM connector.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (ECM - BODY GROUND) 

    Fig 1: Identifying Front View Of Wire Harness Connector
    G06008002Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  2. INSPECT ECM (IGSW VOLTAGE) 
    1. Disconnect the ECM connector.
    2. Turn the ignition switch to ON.
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage 

      VOLTAGE SPECIFICATION

      Tester Connection Switch Condition Specified Condition
      A50-28 (IGSW) - Body ground Ignition switch ON 11 to 14 V
    4. Reconnect the ECM connector.

    NG: Go to step  9

    Fig 2: Identifying ECM Connector Terminal
    G06008003Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  3. INSPECT FUSE (EFI MAIN FUSE) 
    1. Remove the EFI MAIN fuse from the engine room relay block.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Condition
      EFI MAIN fuse Always Below 1 Ω
    3. Reinstall the EFI MAIN fuse.

    NG: CHECK FOR SHORTS IN ALL HARNESSES AND CONNECTORS CONNECTED TO FUSE AND REPLACE FUSE 

    Fig 3: Identifying ECM Connector Terminal
    G06007435Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  4. INSPECT FUSE (EFI NO. 1 FUSE) 
    1. Remove the EFI No. 1 fuse from the engine room relay block.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Condition
      EFI No. 1 fuse Always Below 1 Ω
    3. Reinstall the EFI No. 1 fuse.

    NG: CHECK FOR SHORTS IN ALL HARNESSES AND CONNECTORS CONNECTED TO FUSE AND REPLACE FUSE 

    Fig 4: Identifying Engine Room Relay Block
    G06007302Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  5. INSPECT INTEGRATION RELAY (EFI MAIN RELAY) 
    1. Remove the integration relay from the engine room relay block.
    2. Disconnect the integration relay connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Condition
      1E-1 - 1B-4 Always 10 kΩ or higher
      Always Below 1 Ω (Apply battery voltage terminals 1B-2 and 1B-3)
    4. Reconnect the integration relay connector.
    5. Reinstall the integration relay.

    NG: REPLACE INTEGRATION RELAY 

    Fig 5: Identifying Integration Relay Connector Terminal
    G06008006Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  6. CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY (EFI MAIN RELAY) - ECM) 
    1. Remove the integration relay from the engine room relay block.
    2. Disconnect the integration relay connector.
    3. Disconnect the ECM connector.
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open) 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Condition
      1B-4 - A50-1 (+B2) Always Below 1 Ω
      1B-4 - A50-2 (+B) Always Below 1 Ω
      1B-2 - A50-44 (MREL) Always Below 1 Ω

      Standard Resistance (Check for Short) 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Condition
      1B-4 or A50-2 (+B2) - Body ground Always 10 kΩ or higher
      1B-4 or A50-1 (+B) - Body ground Always 10 kΩ or higher
      1B-2 or A50-44 (MREL) - Body ground Always 10 kΩ or higher
    5. Reconnect the ECM connector.
    6. Reconnect the integration relay connector.
    7. Reinstall the integration relay.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (INTEGRATION RELAY (EFI MAIN RELAY) - ECM) 

    Fig 6: Identifying Engine Room Relay Block Connector Terminal
    G06008007Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  7. CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY (EFI MAIN RELAY) BATTERY) 
    1. Remove the integration relay from the engine room relay block.
    2. Disconnect the integration relay connector.
    3. Disconnect the negative battery terminal.
    4. Disconnect the positive battery terminal.
    5. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open) 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Condition
      1E-1 - Battery positive terminal Always Below 1 Ω

      Standard Resistance (Check for Short) 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Condition
      1E-1 or Battery positive terminal - Body ground Always 10 kΩ or higher
    6. Reconnect the integration relay connector.
    7. Reinstall the integration relay.
    8. Reconnect the positive battery terminal,
    9. Reconnect the negative battery terminal.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (INTEGRATION RELAY (EFI MAIN RELAY) - BATTERY) 

    Fig 7: Identifying Engine Room Relay Block Connector Terminal
    G06007540Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  8. CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY (EFI MAIN RELAY) - BODY GROUND) 
    1. Remove the integration relay from the engine room relay block.
    2. Disconnect the integration relay connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Condition
      1B-3 - Body ground Always Below 1 Ω
    4. Reconnect the integration relay connector.
    5. Reinstall the integration relay.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (INTEGRATION RELAY (EFI MAIN RELAY) - BODY GROUND) 

    Fig 8: Identifying Engine Room Relay Block Connector Terminal
    G06007540Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: PROCEED TO NEXT INSPECTION PROCEDURE SHOWN IN PROBLEM SYMPTOMS TABLE  (See PROBLEM SYMPTOMS TABLE )

  9. INSPECT FUSE (IGN FUSE) 
    1. Remove the IGN fuse from the instrument panel junction block.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Condition
      IGN fuse Always Below 1 Ω
    3. Reinstall the IGN fuse. NG

    NG: CHECK FOR SHORTS IN ALL HARNESSES AND CONNECTORS CONNECTED TO FUSE AND REPLACE FUSE 

    Fig 9: Identifying Instrument Panel Junction Block Connector Terminal
    G06007546Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  10. INSPECT FUSE (IG2 FUSE) 
    1. Remove the IG2 fuse from the engine room relay block.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Condition
      IG2 fuse Always Below 1 Ω
    3. Reinstall the IG2 fuse.

    NG: CHECK FOR SHORTS IN ALL HARNESSES AND CONNECTORS CONNECTED TO FUSE AND REPLACE FUSE 

    Fig 10: Identifying Engine Room Relay Block
    G06008011Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  11. INSPECT INTEGRATION RELAY (IG2 RELAY) 
    1. Remove the integration relay from the engine room relay block.
    2. Disconnect the integration relay connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Condition
      1E-1 - 1A-4 Always 10 kΩ or higher
      Always Below 1 Ω (Apply battery voltage terminals 1A-2 and 1A-3)
    4. Reconnect the integration relay connector.
    5. Reinstall the integration relay.

    NG: REPLACE INTEGRATION RELAY (IG2 RELAY) 

    Fig 11: Identifying Integration Relay Connector Terminal
    G06008006Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  12. CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY (IG2 RELAY) - ECM) 
    1. Disconnect the ECM connector.
    2. Remove the integration relay from the engine room relay block.
    3. Disconnect the integration relay connector.
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open) 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Condition
      1A-4 - A50-28 (IGSW) Always Below 1 Ω

      Standard Resistance (Check for Short) 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Condition
      1A-4 or A50-28 (IGSW) - Body ground Always 10 kΩ or higher
    5. Reconnect the ECM connector.
    6. Reconnect the integration relay connector.
    7. Reinstall the integration relay.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (INTEGRATION RELAY (IG2 RELAY) - ECM) 

    Fig 12: Identifying Engine Room Relay Block Connector Terminal
    G06008013Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  13. CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY (IG2 RELAY) - BATTERY) 
    1. Remove the integration relay from the engine room relay block.
    2. Disconnect the integration relay connector.
    3. Disconnect the negative battery terminal.
    4. Disconnect the positive battery terminal.
    5. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open) 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Condition
      1E-1 - Battery positive terminal Always Below 1 Ω

      Standard Resistance (Check for Short) 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Condition
      1E-1 or Battery positive terminal - Body ground Always 10 kΩ or higher
    6. Reconnect the integration relay connector.
    7. Reinstall the integration relay.
    8. Reconnect the positive battery terminal,
    9. Reconnect the negative battery terminal.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (INTEGRATION RELAY (IG2 RELAY) - BATTERY) 

    Fig 13: Identifying Engine Room Relay Block Connector Terminal
    G06007540Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  14. CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY (IG2 RELAY) - BODY GROUND) 
    1. Remove the integration relay from the engine room relay block.
    2. Disconnect the integration relay connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Condition
      1A-3 - Body ground Always Below 1 Ω

      Result 

      RESULT REFERENCE

      Result Proceed to
      OK (w/o SMART KEY SYSTEM) A
      OK (w/ SMART KEY SYSTEM) B
      NG C
    4. Reconnect the integration relay connector.
    5. Reinstall the integration relay.

    B: Go to step 18 

    C: REPAIR OR REPLACE HARNESS OR CONNECTOR (INTEGRATION RELAY (IG2 RELAY) - BODY GROUND) 

    Fig 14: Identifying Engine Room Relay Block Connector Terminal
    G06007540Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    A: Go to Next Step 

  15. CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY (IG2 RELAY) - IGNITION SWITCH ASSEMBLY) 
    1. Remove the integration relay from the engine room relay block.
    2. Disconnect the integration relay connector.
    3. Disconnect the ignition switch assembly connector.
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open) 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Condition
      1A-2 - E4-6 (IG2) Always Below 1 Ω

      Standard Resistance (Check for Short) 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Condition
      1A-2 or E4-6 (IG2) -Body ground Always 10 kΩ or higher
    5. Reconnect the integration relay connector.
    6. Reinstall the integration relay.
    7. Reconnect the ignition switch assembly connector.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (INTEGRATION RELAY (IG2 RELAY) - IGNITION SWITCH ASSEMBLY) 

    Fig 15: Identifying Engine Room Relay Block Connector Terminal
    G06008016Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  16. INSPECT IGNITION SWITCH ASSEMBLY 
    1. Inspect the ignition switch assembly (See INSPECTION ).

    NG: REPLACE IGNITION SWITCH ASSEMBLY  (See REMOVAL )

    OK: Go to Next Step 

  17. INSPECT FUSE (AM2 FUSE) 
    1. Remove the AM2 fuse from the engine room relay block.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Condition
      AM2 fuse Always Below 1 Ω
    3. Reinstall the AM2 fuse.

    NG: CHECK FOR SHORTS IN ALL HARNESSES AND CONNECTORS CONNECTED TO FUSE AND REPLACE FUSE 

    Fig 16: Identifying Engine Room Relay Block
    G06008017Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - IGNITION SWITCH ASSEMBLY) 

  18. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - INTEGRATION RELAY (IG2 RELAY)) 
    1. Remove the integration relay from the engine room relay block.
    2. Disconnect the integration relay connector.
    3. Disconnect the main body ECU connector.
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Condition
      E51-5 (IG2D) - 1A-2 Always Below 1 Ω
    5. Reconnect the integration relay connector.
    6. Reinstall the integration relay.
    7. Reconnect the main body ECU connector.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (MAIN BODY ECU - INTEGRATION RELAY (IG2 RELAY)) 

    Fig 17: Identifying Engine Room Relay Block Connector Terminal
    G06008018Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  19. INSPECT FUSE (AM2 NO. 2 FUSE) 
    1. Remove the AM2 No. 2 fuse from the engine room relay block.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Condition
      AM2 No. 2 fuse Always Below 1 Ω
    3. Reinstall the AM2 No. 2 fuse.

    NG: CHECK FOR SHORTS IN ALL HARNESSES AND CONNECTORS CONNECTED TO FUSE AND REPLACE FUSE 

    Fig 18: Identifying Engine Room Relay Block Connector Terminal
    G06008019Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  20. CHECK HARNESS AND CONNECTOR (AM2 VOLTAGE) 
    1. Disconnect the main body ECU connector.
    2. Measure the voltage according to the value(s) in the table below.

    Standard Voltage 

    VOLTAGE SPECIFICATION

    Tester Connection Condition Specified Condition
    E50-6 (AM2) - Body ground Always 11 to 14 V
  21. Reconnect the main body ECU connector.

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (MAIN BODY ECU - BATTERY) 

Fig 19: Identifying Main Body ECU Connector Terminal
G06008020Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK: CHECK SMART KEY SYSTEM  (See PROBLEM SYMPTOMS TABLE )

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