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Speed Signal Circuit: Procedure

  1. INSPECT ECU TERMINAL VOLTAGE (INPUT VOLTAGE) 
    1. Disconnect the F15 connector.
      Fig 1: F15 Connector
      GTY354807Courtesy 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
      F15-3 (+S) - Body ground Engine switch on (IG) 4.5 to 14 V
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to Combination Meter Assembly)

      HINT: 

      If any of the ECUs specified in the wiring diagram supplies power to the combination meter assembly, the combination meter assembly will output a waveform.

    NG → See step   5 

    OK: Go to next step 

  2. INSPECT COMBINATION METER ASSEMBLY (OUTPUT VOLTAGE) 
    1. Reconnect the F15 connector.
    2. Disconnect the A44 connector.
      Fig 2: F15 & A44 Connectors
      GTY355196Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      A44-11 (SP1) - Body ground Engine switch on (IG) 11 to 14 V
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to Skid Control ECU)

    NG → See step   4 

    OK: Go to next step 

  3. INSPECT SKID CONTROL ECU (INPUT WAVEFORM) 
    1. Check the input waveform.
      Fig 3: F15 Connector & Waveform
      GTY353513Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. Reconnect the A44 connector.
      2. Remove the combination meter assembly with the connector(s) still connected.
      3. Connect an oscilloscope to terminal F15-4 (SI) and body ground.
      4. Turn the engine switch on (IG).
      5. Turn the wheel slowly.
      6. Check the signal waveform according to the condition(s) in the table below.
        Item Condition
        Tool setting 5 V/DIV., 20 ms./DIV.
        Vehicle condition Driving at approx. 20 km/h (12 mph)
        TEXT IN ILLUSTRATION

        *1 Component with harness connected
        (Combination Meter Assembly)

        OK

        The waveform is displayed as shown in the illustration.

        HINT: 

        When the system is functioning normally, one wheel revolution generates 4 pulses. As the vehicle speed increases, the width indicated by (A) in the illustration narrows.

    NG → See step   16 

    OK → See step   17 

  4. CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - SKID CONTROL ECU) 
    1. Disconnect the F15 and A44 connectors.
      Fig 4: F15 and A44 Connectors
      GTY353697Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A44-11 (SP1) - F15-4 (SI) Always Below 1 Ω
      A44-11 (SP1) - Body ground Always 10 kΩ or higher
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to Combination Meter Assembly)
      *2 Front view of wire harness connector
      (to Skid Control ECU)

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   17 

  5. CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - JUNCTION BLOCK) 
    1. Disconnect the F93 connector.
      Fig 5: F93 & F15 Connector
      GTY348358Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      F15-3 (+S) - F93-57 Always Below 1 Ω
      F15-3 (+S) - Body ground Always 10 kΩ or higher
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to Junction Block)
      *2 Front view of wire harness connector
      (to Combination Meter Assembly)

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  6. CHECK HARNESS AND CONNECTOR (JUNCTION BLOCK) 
    1. Inspect for a short in the circuit that is connected to the junction block connector shown in the wiring diagram.

      HINT: 

      If voltage is not present, it is possible that an ECU or circuit has a malfunction. The malfunctioning ECU or circuit will be diagnosed in the following steps.

      1. Disconnect the junction block connector.
        Fig 6: Junction Block Connector
        GTY353971Courtesy 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
        F93-87 - Body ground Engine switch on (IG) 4.5 to 14 V
        F93-37 - Body ground Engine switch on (IG) 4.5 to 14 V
        F93-27 - Body ground Engine switch on (IG) 4.5 to 14 V
        F93-47 - Body ground Engine switch on (IG) 4.5 to 14 V
        F93-67 - Body ground Engine switch on (IG) 4.5 to 14 V
        F93-77 - Body ground Engine switch on (IG) 4.5 to 14 V
        F93-88 - Body ground Engine switch on (IG) 4.5 to 14 V
        TEXT IN ILLUSTRATION

        *1 Front view of wire harness connector
        (to Junction Block)

        Result

        Result Proceed to
        Voltage is not present in one circuit. A
        Voltage is present in all the circuits. B

    B → REPLACE JUNCTION BLOCK 

    A: Go to next step 

  7. SYSTEM CHECK 
    1. Select the circuit for which voltage was not present in step 6.

      Result

      Tester Connection System that Uses the Circuit Proceed to
      F93-87 - Body ground Tire Pressure Warning System*1 A
      F93-37 - Body ground Smart Access System with Push-button Start System B
      F93-27 - Body ground Separate Type Amplifier System*2 B
      F93-47 - Body ground Audio and Visual System or Navigation System*3 B
      F93-67 - Body ground SFI System, Automatic Transaxle System B
      F93-77 - Body ground Wiper and Washer System*4 B
      F93-88 - Body ground Lexus Enform System*5 C
      • *1: w/ Tire Pressure Warning System
      • *2: for Separate Type Amplifier System
      • *3: w/ Navigation System
      • *4: w/ Auto Wiper System
      • *5: w/ Manual (SOS) Switch

    B → See step   9 

    C → See step   15 

    A: Go to next step 

  8. CHECK HARNESS AND CONNECTOR (TIRE PRESSURE WARNING ECU CIRCUIT) 
    1. Disconnect the F53 connector.
      Fig 7: F53 Connector
      GTY352502Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      F53-2 (SPD) - Body ground Always 10 kΩ or higher
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to Tire Pressure Warning ECU)

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   20 

  9. SYSTEM CHECK 
    1. Select the circuit for which voltage was not present in step 6.

      Result

      Tester Connection System that Uses the Circuit Proceed to
      F93-37 - Body ground Smart Access System with Push-button Start System A
      F93-27 - Body ground Separate Type Amplifier System*1 B
      F93-47 - Body ground Audio and Visual System or Navigation System*2 C
      F93-67 - Body ground SFI System, Automatic Transaxle System D
      F93-77 - Body ground Auto Wiper System*3 E
      • *1: for Separate Type Amplifier System
      • *2: w/ Navigation System
      • *3: w/ Auto Wiper System

    B → See step   11 

    C → See step   12 

    D → See step   13 

    E → See step   14 

    A: Go to next step 

  10. CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU CIRCUIT) 
    1. Disconnect the F8 connector.
      Fig 8: F8 Connector
      GTY350748Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      F8-23 (SPD) - Body ground Always 10 kΩ or higher
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to Power Management Control ECU)

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   18 

  11. CHECK HARNESS AND CONNECTOR (STEREO COMPONENT AMPLIFIER CIRCUIT) 
    1. Disconnect the O15*1 or O33*2 connector.
      Fig 9: O15*1 or O33*2 Connector
      GTY355329Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      O15-2 (SPD)*1 - Body ground Always 10 kΩ or higher
      O33-11 (SPD)*2 - Body ground Always 10 kΩ or higher
      • *1: w/ Navigation System
      • *2: w/o Navigation System
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to Stereo Component Amplifier (w/ Navigation System))
      *2 Front view of wire harness connector
      (to Stereo Component Amplifier (w/o Navigation System))

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   24 

  12. CHECK HARNESS AND CONNECTOR (RADIO RECEIVER, DISPLAY AND NAVIGATION MODULE DISPLAY) 
    1. Disconnect the G9 or G4*1 connector.
      Fig 10: G9 or G4*1 Connector
      GTY355798Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      G9-3 (SPD) - Body ground Always 10 kΩ or higher
      G4-18 (SPD)*1 - Body ground Always 10 kΩ or higher
      • *1: w/ Navigation System
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to Radio Receiver)
      *2 Front view of wire harness connector
      (to Display and Navigation Module Display)

      Result

      Result Proceed to
      OK (for Radio Receiver Circuit) A
      OK (for Display and Navigation Module Display Circuit for DVD) B
      OK (for Display and Navigation Module Display Circuit for HDD) C
      NG D

    B → See step   25 

    C → See step   27 

    D → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    A → See step   23 

  13. CHECK HARNESS AND CONNECTOR (ECM CIRCUIT, TCM CIRCUIT) 
    1. Disconnect the A43 or D2 connector.
      Fig 11: A43 or D2 Connector
      GTY349487Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A43-13 (SPD) - Body ground Always 10 kΩ or higher
      D2-3 (SPD) - Body ground Always 10 kΩ or higher
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to ECM)
      *2 Front view of wire harness connector
      (to TCM)

      Result

      Result Proceed to
      OK (for 2GR-FE SFI System) A
      OK (for U660E Automatic Transaxle System) B
      OK (for U660F Automatic Transaxle System) C
      NG D

    B → See step   26 

    C → See step   21 

    D → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    A → See step   19 

  14. CHECK HARNESS AND CONNECTOR (WINDSHIELD WIPER SWITCH ASSEMBLY CIRCUIT) 
    1. Disconnect the F42 connector.
      Fig 12: F42 Connector
      GTY351283Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      F42-6 (SPD) - Body ground Always 10 kΩ or higher
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to Windshield Wiper Switch Assembly)

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   22 

  15. CHECK HARNESS AND CONNECTOR (DCM (TELEMATICS TRANSCEIVER) CIRCUIT) 
    1. Disconnect the G25 connector.
      Fig 13: Identifying G25 Connector
      GTY271716Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      G25-10 (SPDP) - Body ground Always 10 kΩ or higher
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to DCM (Telematics Transceiver))

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   28 

  16. REPLACE SKID CONTROL ECU. Refer to  REMOVAL 
  17. REPLACE COMBINATION METER ASSEMBLY. Refer to  REMOVAL 
  18. REPLACE POWER MANAGEMENT CONTROL ECU. Refer to  REMOVAL 
  19. REPLACE ECM (for 2GR-FE). Refer to  REMOVAL 
  20. REPLACE TIRE PRESSURE WARNING ECU. Refer to  REMOVAL 
  21. REPLACE TCM (for U660F). Refer to  REMOVAL 
  22. REPLACE WINDSHIELD WIPER SWITCH ASSEMBLY. Refer to  REMOVAL 
  23. REPLACE RADIO RECEIVER. Refer to  REMOVAL 
  24. REPLACE STEREO COMPONENT AMPLIFIER. Refer to  REMOVAL 
  25. REPLACE DISPLAY AND NAVIGATION MODULE DISPLAY (for DVD). Refer to  REMOVAL 
  26. REPLACE TCM (for U660E). Refer to  REMOVAL 
  27. REPLACE DISPLAY AND NAVIGATION MODULE DISPLAY (for HDD). Refer to  REMOVAL 
  28. REPLACE DCM (TELEMATICS TRANSCEIVER). Refer to  REMOVAL