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Inspection Procedure

  1. INSPECT ECM (+B VOLTAGE) 
    1. Turn the ignition switch ON.
    2. Measure the voltage between the specified terminals of the E5 and E7 ECM connectors.

      Standard: 

      ECM (+B VOLTAGE)

      Tester Connection Specified Condition
      +B (E5-1) - E1 (E7-1) 9 to 14 V
      Fig 1: Inspecting ECM (+B Voltage)
      G03008342Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    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 E7 ECM connector.
    2. Check the resistance between the wire harness side connectors.

      Standard (Check for open): 

      ECM - BODY GROUND

      Tester Connection Specified Condition
      E1 (E7-1) - Body ground Below 1 Ω
      Fig 2: Checking Harness And Connector (ECM - Body Ground)
      G03008343Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    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 the specified terminals of the E5 and E7 ECM connectors.

      Standard: 

      ECM (IGSW VOLTAGE)

      Tester Connection Specified Condition
      IGSW (E5-9) - E1 (E7-1) 9 to 14 V
      Fig 3: Inspecting ECM (IGSW Voltage)
      G03008344Courtesy 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 instrument panel J/B.
    2. Check for continuity in the IGN fuse. Standard: Continuity
    3. Reinstall the IGN fuse.
      Fig 4: Checking Fuse (IGN Fuse)
      G03008345Courtesy 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 the chart below.

      Standard: 

      IGNITION OR STARTER SWITCH ASSY

      Switch Terminal No. Resistance
      LOCK All Terminals No continuity
      ACC 1 - 2 Continuity
      ON 2 - 3, 2 - 4, 3 - 4, 6 - 7 Continuity
      START 1 - 2, 1 - 4, 2 - 4, 6 - 7, 6 - 8, 7 - 8 Continuity
      Fig 5: Inspecting Ignition Or Starter Switch Assy
      G03008346Courtesy 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 the specified terminals of the E5 and E7 ECM connectors.

      Standard: 

      ECM (MREL VOLTAGE)

      Tester Connection Specified Condition
      MREL (E5-8) - E1 (E7-1) 9 to 14 V
      Fig 6: Inspecting ECM (MREL Voltage)
      G03008347Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: REPLACE ECM (See  REPLACEMENT  ) 
    2. OK: Go to next step. 
  7. CHECK FUSE (EFI NO. 1 FUSE) 
    1. Remove the EFI No. 1 fuse from the fusible link block.
    2. Check the resistance in the EFI No. 1 fuse.

      Standard: Below 1 D, 

    3. Reinstall the EFI No. 1 fuse.
      Fig 7: Checking Fuse (EFI No. 1 Fuse)
      G03008348Courtesy 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 R/B.
    2. Inspect the EFI relay.

      Standard: 

      EFI RELAY

      Tester Connection Specified Condition
      1 - 2 Continuity
      3 - 5 No continuity
      3 - 5 Continuity (Apply battery voltage terminals 1 and 2)
      Fig 8: Inspecting EFI Relay
      G03008349Courtesy 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 R/B.
        2. Fig 9: Removing EFI Relay From Engine Room R/B
        G03008350Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Disconnect the E5 ECM connector.
      3. Check the resistance between the wire harness side connectors.

        Standard (Check for open): 

        EFI RELAY - ECM (CHECK FOR OPEN)

        Tester Connection Specified Condition
        EFI relay (1) - MREL (E5-8) Below 1 Ω

        Standard (Check for short): 

        EFI RELAY - ECM (CHECK FOR SHORT)

        Tester Connection Specified Condition
        EFI relay (1) or MREL (E5-8) - Body ground 10 kΩ or higher
        Fig 10: Checking Harness And Connector (EFI Relay - ECM, EFI Relay - Body Ground)
        G03008351Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      4. Reinstall the EFI relay.
      5. Reconnect the ECM connector.
    2. Check the harness and the connector between the EFI relay and the body ground.
      1. Remove the EFI relay from the engine room R/B.
      2. Check the resistance between the wire harness side connector and the body ground.

        Standard (Check for open): 

        EFI RELAY - BODY GROUND (CHECK FOR OPEN)

        Tester Connection Specified Condition
        EFI relay (2) - Body ground Below 1 Ω
      3. 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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