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Fuel Injector Circuit: Procedure

  1. CHECK INJECTOR ASSEMBLY (POWER SOURCE) 
    Fig 1: Identifying Fuel Injector Connector Terminals
    GTY143308Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the fuel injector connector.
    2. Turn the engine switch on (IG).
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Cylinder Tester Connection Switch Condition Specified Condition
      No. 1 a5-2 - Ground Engine switch on (IG) 11 to 14 V
      No. 2 a1-2 - Ground Engine switch on (IG) 11 to 14 V
      No. 3 a6-2 - Ground Engine switch on (IG) 11 to 14 V
      No. 4 a2-2 - Ground Engine switch on (IG) 11 to 14 V
      No. 5 a7-2 - Ground Engine switch on (IG) 11 to 14 V
      No. 6 a3-2 - Ground Engine switch on (IG) 11 to 14 V
      No. 7 a8-2 - Ground Engine switch on (IG) 11 to 14 V
      No. 8 a4-2 - Ground Engine switch on (IG) 11 to 14 V

    NG → See step   4 

    OK: Go to next step 

  2. INSPECT FUEL INJECTOR ASSEMBLY 
    1. Inspect the fuel injector. Refer to INSPECTION .

    NG → See step   6 

    OK: Go to next step 

  3. CHECK HARNESS AND CONNECTOR (FUEL INJECTOR ASSEMBLY - ECM) 
    Fig 2: Identifying Fuel Injector And C53 ECM Connector Terminals
    GTY210793Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the fuel injector connector.
    2. Disconnect the C53 ECM connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Cylinder Tester Connection Condition Specified Condition
      No. 1 a5-1 - Body ground Always 10 kΩ or higher
      a5-1 - C53-86 (#10) Always Below 1 Ω
      No. 2 a1-1 - Body ground Always 10 kΩ or higher
      a1-1 - C53-109 (#20) Always Below 1 Ω
      No. 3 a6-1 - Body ground Always 10 kΩ or higher
      a6-1 - C53-85 (#30) Always Below 1 Ω
      No. 4 a2-1 - Body ground Always 10 kΩ or higher
      a2-1 - C53-108 (#40) Always Below 1 Ω
      No. 5 a7-1 - Body ground Always 10 kΩ or higher
      a7-1 - C53-84 (#50) Always Below 1 Ω
      No. 6 a3-1 - Body ground Always 10 kΩ or higher
      a3-1 - C53-107 (#60) Always Below 1 Ω
      No. 7 a8-1 - Body ground Always 10 kΩ or higher
      a8-1 - C53-83 (#70) Always Below 1 Ω
      No. 8 a4-1 - Body ground Always 10 kΩ or higher
      a4-1 - C53-106 (#80) Always Below 1 Ω

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   7 

  4. INSPECT FUSE (INJ, IG2 MAIN) 
    Fig 3: Identifying INJ And IG2 Main Fuses
    GTY148128Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Remove the INJ fuse and IG2 MAIN fuse from the engine room relay block.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      INJ fuse Always Below 1 Ω
      IG2 fuse Always Below 1 Ω

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

    OK: Go to next step 

  5. INSPECT INTEGRATION RELAY (IG2) 
    1. Inspect the integration relay. Refer to ON-VEHICLE INSPECTION - Step 2 .

    NG → REPLACE INTEGRATION RELAY 

    OK → REPAIR OR REPLACE HARNESS OR CONNECTOR (INTEGRATION RELAY - FUEL INJECTOR ASSEMBLY) 

  6. REPLACE FUEL INJECTOR ASSEMBLY. Refer to  REMOVAL 
  7. REPLACE ECM. Refer to  REMOVAL 
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