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ECM Power Source Circuit [08/2014 - ]: 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
      D23-49 (E1) - Body ground Always Below 1 Ω

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  2. CHECK TERMINAL VOLTAGE (IGSW VOLTAGE) 
    1. Disconnect the ECM connector.
      GTY397661Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Turn the engine switch on (IG).
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      A22-32 (IGSW) - Body ground Engine switch on (IG) 11 to 14 V
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to ECM)

    NG → See step   6 

    OK: Go to next step 

  3. INSPECT NO. 1 INTEGRATION RELAY (EFI MAIN RELAY) 
    1. Inspect the No. 1 integration relay (EFI MAIN relay). Refer to INSPECTION [08/2014 - ] .

    NG → See step   11 

    OK: Go to next step 

  4. CHECK HARNESS AND CONNECTOR (NO. 1 INTEGRATION RELAY - ECM) 
    1. Remove the No. 1 integration relay from the engine room relay block and junction block assembly.
    2. Disconnect the ECM connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      1C-9 - A22-2 (+B) Always Below 1 Ω
      1C-10 - A22-3 (+B2) Always Below 1 Ω
      1C-7 - A22-46 (MREL) Always Below 1 Ω
      1C-9 or A22-2 (+B) - Body ground Always 10 kΩ or higher
      1C-10 or A22-3 (+B2) - Body ground Always 10 kΩ or higher
      1C-7 or A22-46 (MREL) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  5. CHECK TERMINAL VOLTAGE (POWER SOURCE OF NO. 1 INTEGRATION RELAY) 
    1. Remove the No. 1 integration relay from the engine room relay block and junction block assembly.
      GTY320252Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      1B-1 - Body ground Always 11 to 14 V
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to No. 1 Integration Relay)

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - NO. 1 INTEGRATION RELAY) 

    OK → See step   13 

  6. INSPECT NO. 1 INTEGRATION RELAY (IG2 RELAY) 
    1. Inspect the No. 1 integration relay (IG2 relay). Refer to INSPECTION [08/2014 - ] .

    NG → See step   12 

    OK: Go to next step 

  7. CHECK HARNESS AND CONNECTOR (NO. 1 INTEGRATION RELAY - ECM) 
    1. Remove the No. 1 integration relay from the engine room relay block and junction block assembly.
    2. Disconnect the ECM connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      1C-1 - A22-32 (IGSW) Always Below 1 Ω
      1C-1 or A22-32 (IGSW) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  8. CHECK TERMINAL VOLTAGE (POWER SOURCE OF NO. 1 INTEGRATION RELAY) 
    1. Remove the No. 1 integration relay from the engine room relay block and junction block assembly.
      GTY316021Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      1D-3 - Body ground Always 11 to 14 V
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to No. 1 Integration Relay)

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - NO. 1 INTEGRATION RELAY) 

    OK: Go to next step 

  9. CHECK HARNESS AND CONNECTOR (NO. 1 INTEGRATION RELAY - BODY GROUND) 
    1. Remove the No. 1 integration relay from the engine room relay block and junction block assembly.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      1E-2 - Body ground Always Below 1 Ω

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  10. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - NO. 1 INTEGRATION RELAY 
    1. Disconnect the certification ECU (smart key ECU assembly) connector.
    2. Remove the No. 1 integration relay from the engine room relay block and junction block assembly.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A36-9 (IG2D) - 1C-8 Always Below 1 Ω
      A36-9 (IG2D) or 1C-8 - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   14 

  11. REPLACE NO. 1 INTEGRATION RELAY (EFI MAIN RELAY). Refer to  REMOVAL [08/2014 - ] 
  12. REPLACE NO. 1 INTEGRATION RELAY (IG2 RELAY). Refer to  REMOVAL [08/2014 - ] 
  13. PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE [08/2014 - ] 
  14. GO TO SMART ACCESS SYSTEM WITH PUSH-BUTTON START. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [08/2014 - ] 
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