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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.

    Standard: 

    SPECIFIED CONDITION

    Symbols (Terminal No.) Specified condition
    +B (E4-1) - E1 (E6-1) 9 to 14 V
    Fig 1: Measuring Voltage Between Terminals Of E4 & E6 ECM Connectors
    G02629061Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN ON  PROBLEM SYMPTOMS TABLE  
    2. NG: GO TO NEXT STEP. 
  2. CHECK HARNESS AND CONNECTOR (ECM - BODY GROUND) 
    1. Disconnect the E6 ECM connector.
    2. Check for continuity between the wire harness side connectors.

      Standard (Check for open): 

      SPECIFIED CONDITION

      Symbols (Terminal No.) Specified condition
      E1 (E6-1) - Body ground Continuity
    3. Reconnect the ECM connector.
    Fig 2: Disconnecting E6 ECM Connector
    G02629062Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 
    2. OK: GO TO NEXT STEP. 
  3. INSPECT ECM (GSW VOLTAGE) 
    1. Turn the ignition switch ON.
    2. Measure the voltage between terminals of the E4 and E6 ECM connectors.

    Standard: 

    SPECIFIED CONDITION

    Symbols (Terminal No.) Specified condition
    IGSW (E4-9) - E1 (E6-1) 9 to 14 V
    Fig 3: Measuring Voltage Between Terminals Of E4 & E6 ECM Connectors
    G02629063Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    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. Check for continuity in the IGN fuse

    Standard: Continuity 

    Fig 4: Identifying IGN Fuse
    G02629064Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    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 TERMINAL RESISTANCE  .

    Standard: 

    TERMINAL RESISTANCE

    Switch Terminal No. Resistance
    LOCK All terminals 1 MΩ or more
    ACC 1 - 3 1 Ω or less
    ON 1 -2, 1 - 3, 2 - 3 5 - 6 1 Ω or less
    START 4 - 5, 4 - 6, 5 - 6 1 - 2 1Ω or less
    Fig 5: Checking Continuity Between Connector Terminals
    G02629065Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    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

    Standard: 

    SPECIFIED CONDITION

    Symbols (Terminal No.) Specified condition
    MREL (E4-8) - E1 (E6-1) 9 to 14 V
    Fig 6: Measuring Voltage Between Terminals Of E4 & E6 ECM Connectors
    G02629066Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    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: Removing EFI No. 1 Fuse From Engine Room J/B
    G02629067Courtesy 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.

      Standard: 

      Fig 8: Removing EFI Relay From Engine Room J/B
      G02629068Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      SPECIFIED CONDITION

      Terminal No. Specified condition
      1 - 2 Continuity
      3 - 5 No Continuity
      Continuity
      (Apply battery voltage terminals 1 and 2)
    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. Disconnect the E4 ECM connector,
      3. Check for continuity between the wire harness side connectors.
      Fig 9: Removing EFI Relay From Engine Room J/B
      G02629069Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard (Check for open): 

      SPECIFIED CONDITION

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

      Standard (Check for short): 

      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.
      Fig 10: Reconnecting ECM Connector
      G02629070Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard (Check for open): 

      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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