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Inspection Procedure

  1. INSPECT ECM(+B VOLTAGE) 
    1. Turn the ignition switch ON.
    2. Measure the voltage between terminals of the E4 and E6 ECM connectors.
      Fig 1: Identifying E4 & E6 ECM Connector Terminals For Measuring Voltage
      G02933339Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard: 

      SYMBOLS SPECIFIED CONDITION

      Symbols (Terminal No.) Specified condition
      +B (E4-1) - E1 (E6-1) 9 to 14 V
    1. OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN ON PROBLEM SYMPTOMS TABLE (See  PROBLEM SYMPTOMS TABLE  ) 
    2. NG: Go to next step. 
  2. CHECK HARNESS AND CONNECTOR (ECM - BODY GROUND) 
    1. Disconnect the E6 ECM connector.
      2. Fig 2: Disconnecting E6 ECM Connector
      G02933340Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Check for continuity between the wire harness side connectors.

      Standard (Check for open): 

      SYMBOL SPECIFIED CONDITION (FOR OPEN)

      Symbols (Terminal No.) Specified condition
      E1 (E6-1) - Body ground Continuity
    3. Reconnect the ECM connector.
    1. NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 
    2. OK: Go to next step. 
  3. INSPECT ECM (IGSW VOLTAGE) 
    1. Turn the ignition switch ON.
    2. Measure the voltage between terminals of the E4 and E6 ECM connectors.
      Fig 3: Identifying E4 & E6 ECM Connector Terminal For Measuring Voltage
      G02933341Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard: 

      SYMBOLS SPECIFIED CONDITION

      Symbols (Terminal No.) Specified condition
      IGSW (E4-9) - E1 (E6-1) 9 to 14 V
    1. OK: Go to step   6 
    2. NG: Go to next step. 
  4. CHECK FUSE (IGN FUSE) 
    1. Remove the IGN fuse from the driver side J/B.
      2. Fig 4: Identifying IGM Fuse For Removal
      G02933342Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Check for continuity in the IGN fuse.

      Standard: Continuity 

    1. NG: CHECK FOR SHORT IN ALL HARNESSES AND COMPONENTS CONNECTED FUSE 
    2. OK: Go to next step. 
  5. INSPECT IGNITION OR STARTER SWITCH ASSY 
    1. Check for continuity between the connector terminals shown in the chart below.
      Fig 5: Identifying Connector Terminals For Checking Continuity
      G02933343Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard: 

      TERMINAL RESISTANCE

      Switch Terminal No. Resistance
      LOCK All terminals 1MΩ or more
      ACC 1 - 3 1Ω or less
      ON 1 - 2, 1 - 3, 2 - 3 1Ω or less
      ON 5 - 6 1Ω or less
      START5 4 - 5, 4 - 6 5 - 6 1Ω or less
      START5 1 - 2 1Ω or less
    1. NG: REPLACE IGNITION OR STARTER SWITCH ASSY 
    2. OK: CHECK AND REPAIR HARNESS AND CONNECTOR (BATTERY - IGNITION SWITCH, IGNITION SWITCH - ECM) 
  6. INSPECT ECM (MREL VOLTAGE) 
    1. Turn the ignition switch ON.
    2. Measure the voltage between terminals of the E4 and E6 ECM connectors.
      Fig 6: Identifying E4 & E6 ECM Connector Terminals For Measuring Voltage
      G02933344Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard: 

      SYMBOLS SPECIFIED CONDITION

      Symbols (Terminal No.) Specified condition
      MREL (E4-8) - E1 (E6-1) 9 to 14 V
    1. NG: CHECK AND REPLACE ECM (See  ELECTRONIC CIRCUIT INSPECTION PROCEDURE  ) 
    2. OK: Go to next step. 
  7. CHECK FUSE (EFI NO. 1 FUSE) 
    1. Remove the EFI No. 1 fuse from the engine room J/B.
    2. Check for continuity in the EFI No. 1 fuse.

      Standard: Continuity 

    3. Reinstall the EFI No. 1 fuse.
      Fig 7: Identifying EFI No. 1 Fuse For Removal
      G02933345Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: CHECK FOR SHORT IN ALL HARNESSES AND COMPONENTS CONNECTED FUSE 
    2. OK: Go to next step. 
  8. INSPECT EFI RELAY 
    1. Remove the EFI relay from the engine room J/B.
    2. Inspect the EFI relay.
      Fig 8: Inspecting EFI Relay
      G02933346Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard: 

      Fig 9: Terminal Specified Condition Table
      G02933347Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Reinstall the EFI relay.
    1. NG: REPLACE EFI RELAY 
    2. OK: Go to next step. 
  9. CHECK HARNESS AND CONNECTOR (EFI RELAY - ECM, EFI RELAY - BODY GROUND) 
    1. Check the harness and connector between the EFI relay and ECM connector.
      1. Remove the EFI relay from the engine room J/B.
        2. Fig 10: Identifying EFI Relay For Removal
        G02933348Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Disconnect the E4 ECM connector.
        3. Fig 11: Disconnecting E4 ECM Connector
        G02933349Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. Check for continuity between the wire harness side connectors.

        Standard (Check for open): 

        SYMBOLS SPECIFIED CONDITION

        Symbols (Terminal No.) Specified condition
        EFI relay (1) - MREL (E4-8) Continuity

        Standard (Check for short): 

        SYMBOLS SPECIFIED CONDITION

        Symbols (Terminal No.) Specified condition
        EFI relay (1) or MREL (E4-8) - Body ground No continuity
    2. Reinstall the EFI relay.
    3. Reconnect the ECM connector.
    4. Check the harness and the connector between the EFI relay and the body ground.
      1. Remove the EFI relay from the engine room J/B.
      2. Check for continuity between the wire harness side connector and the body ground.

        Standard (Check for open): 

        SYMBOLS SPECIFIED CONDITION

        Symbols (Terminal No.) Specified condition
        EFI relay (2) - Body ground Continuity
    5. Reinstall the EFI relay.
    1. OK: REPAIR OR REPLACE HARNESS OR CONNECTOR 
    2. NG: CHECK AND REPAIR HARNESS AND CONNECTOR (TERMINAL +B OF ECM - BATTERY POSITIVE TERMINAL) 
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