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Home >> Toyota >> 2012 >> Matrix Base, Automatic Trans >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System (2ZR-FE) (Diagnostic Codes (P1604 - P2A00) & Circuit Tests) >> SFI System >> Circuit Tests >> ECM Power Source Circuit >> Procedure
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ECM Power Source Circuit: Procedure

  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

      Tester Connection Condition Specified Condition
      B29-105 (E1) - Body ground Always Below 1 Ω
    3. Reconnect the ECM connector.

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

    OK: Go to next step 

  2. INSPECT ECM (IGSW VOLTAGE) 
    1. Disconnect the ECM connector.
      Fig 1: Inspecting ECM (IGSW Voltage) Connector Terminals
      GTY292866Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Turn the ignition switch to ON.
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      A37-27 (IGSW) - Body ground Ignition switch ON 11 to 14 V
    4. Reconnect the ECM connector.

    NG → See step   9 

    OK: Go to next step 

  3. INSPECT FUSE (EFI MAIN FUSE) 
    1. Remove the EFI MAIN fuse from the engine room relay block.
      Fig 2: Identifying EFI MAIN Fuse
      GTY187616Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      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 

    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.
      Fig 3: Identifying EFI No. 1 Fuse
      GTY193287Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      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 

    OK: Go to next step 

  5. INSPECT INTEGRATION RELAY (EFI MAIN RELAY) 
    1. Inspect the integration relay (EFI MAIN relay). Refer to INSPECTION .

    NG → See step   18 

    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)

      Tester Connection Condition Specified Condition
      1B-4 - A37-1 (+B2) Always Below 1 Ω
      1B-4 - A37-2 (+B) Always Below 1 Ω
      1B-2 - A37-44 (MREL) Always Below 1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      1B-4 or A37-1 (+B2) - Body ground Always 10 kΩ or higher
      1B-4 or A37-2 (+B) - Body ground Always 10 kΩ or higher
      1B-2 or A37-44 (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) 

    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)

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

      Standard Resistance (Check for Short)

      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) 

    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

      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) 

    OK → See step   21 

  9. INSPECT FUSE (IGN FUSE) 
    1. Remove the IGN fuse from the driver side junction block.
      Fig 4: Identifying IGN Fuse
      GTY215238Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

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

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

    OK: Go to next step 

  10. INSPECT FUSE (IG2 FUSE) 
    1. Remove the IG2 fuse from the engine room relay block.
      Fig 5: Identifying IG2 Fuse
      GTY193288Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      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 

    OK: Go to next step 

  11. INSPECT INTEGRATION RELAY (IG2 RELAY) 
    1. Inspect the integration relay (IG2 relay). Refer to INSPECTION .

    NG → See step   19 

    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)

      Tester Connection Condition Specified Condition
      1A-4 - A37-27 (IGSW) Always Below 1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      1A-4 or A37-27 (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) 

    OK: Go to next step 

  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)

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

      Standard Resistance (Check for Short)

      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) 

    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

      Tester Connection Condition Specified Condition
      1A-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 (IG2 RELAY) - BODY GROUND) 

    OK: 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)

      Tester Connection Condition Specified Condition
      1A-2 - E5-6 (IG2) Always Below 1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      1A-2 or E5-6 (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) 

    OK: Go to next step 

  16. INSPECT IGNITION SWITCH ASSEMBLY 
    1. Inspect the ignition switch assembly. Refer to INSPECTION .

    NG → See step   20 

    OK: Go to next step 

  17. INSPECT FUSE (AM2 NO. 2 FUSE) 
    1. Remove the AM2 No. 2 fuse from the engine room relay block.
      Fig 6: Identifying AM2 No. 2 Fuse
      GTY177926Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      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 

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

  18. REPLACE INTEGRATION RELAY (EFI MAIN RELAY). Refer to  REMOVAL 
  19. REPLACE INTEGRATION RELAY (IG2 RELAY). Refer to  REMOVAL 
  20. REPLACE IGNITION SWITCH ASSEMBLY. Refer to  REMOVAL 
  21. PROCEED TO NEXT INSPECTION PROCEDURE SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE 
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