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Speed Signal Circuit [08/2019 - 08/2022]: Procedure

  1. CHECK ECU TERMINAL VOLTAGE (INPUT VOLTAGE) 
    1. Disconnect the F14 combination meter assembly connector.
    2. Measure the voltage according to the value(s) in the table below.
      GTY891803Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Combination Meter Assembly)

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      F14-17 (+S) - Body ground Ignition switch ON 11 to 14 V

    Result: 

    NG 

    See step  5

    Result: 

    OK 

    See step  2

  2. CHECK COMBINATION METER ASSEMBLY (OUTPUT VOLTAGE) 
    1. For 4WD:
      1. Disconnect the A6 skid control ECU (master cylinder solenoid) connector.
      2. Measure the voltage according to the value(s) in the table below.
        GTY841751Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        *a Front view of wire harness connector
        (to Skid Control ECU (Master Cylinder Solenoid))

        Standard Voltage

        Tester Connection Switch Condition Specified Condition
        A6-12 (SP1) - Body ground Ignition switch ON 11 to 14 V
    2. For 2WD:
      1. Disconnect the A58 skid control ECU (brake actuator assembly) connector.
      2. Measure the voltage according to the value(s) in the table below.
        GTY849504Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        *a Front view of wire harness connector
        (to Skid Control ECU (Brake Actuator Assembly))

        Standard Voltage

        Tester Connection Switch Condition Specified Condition
        A58-14 (SP1) - Body ground Ignition switch ON 11 to 14 V

    Result: 

    NG 

    See step  4

    Result: 

    OK 

    See step  3

  3. CHECK COMBINATION METER ASSEMBLY (SPEED SIGNAL) 
    1. Check the input waveform.
      GTY858328Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Combination Meter Assembly)
      1. Reconnect the F14 combination meter assembly connector.
      2. Remove the combination meter assembly with the connector(s) still connected.
      3. Connect an oscilloscope to terminal F14-18 (SI) and body ground.
      4. Turn the ignition switch to ON.
      5. Check the signal waveform according to the condition(s) in the table below.
        MEASUREMENT CONDITION

        Item Condition
        Terminal No. (Symbol) F14-18 (SI) - Body ground
        Tool setting 5 V/DIV., 20 ms./DIV.
        Condition Driving at approx. 20 km/h (12 mph)

        OK

        The waveform displayed is 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.

      RESULT

      Result Proceed to
      OK A
      NG (for 4WD) B
      NG (for 2WD) C

    Result: 

    A 

    REPLACE COMBINATION METER ASSEMBLY. Refer to  REMOVAL [08/2015 - 08/2022] 

    Result: 

    B 

    REPLACE SKID CONTROL ECU (MASTER CYLINDER SOLENOID). Refer to  DISASSEMBLY [08/2015 - ] 

    Result: 

    C 

    REPLACE SKID CONTROL ECU (BRAKE ACTUATOR ASSEMBLY). Refer to  REMOVAL [08/2019 - ] 

  4. CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - SKID CONTROL ECU) 
    1. Disconnect the F14 combination meter assembly connector.
    2. Disconnect the A6 skid control ECU (master cylinder solenoid)*1 or A58 skid control ECU (brake actuator assembly)*2 connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      F14-18 (SI) - A6-12 (SP1)*1
      F14-18 (SI) - A58-14 (SP1)*2      		 Always Below 1 Ω
      A6-12 (SP1) - Body ground*1
      A58-14 (SP1) - Body ground*2      		 Always 10 kΩ or higher
      1. *1: for 4WD
      2. *2: for 2WD

    Result: 

    OK 

    REPLACE COMBINATION METER ASSEMBLY. Refer to  REMOVAL [08/2015 - 08/2022] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  5. CHECK HARNESS AND CONNECTOR (EACH ECU - COMBINATION METER ASSEMBLY) 
    1. Disconnect the F14 combination meter assembly connector.
    2. Disconnect the F113 certification ECU (smart key ECU assembly) connector.*1
    3. Disconnect the N19 voltage inverter assembly connector.*2
    4. Disconnect the F50 ECM connector.
    5. Disconnect the N25 stereo component amplifier assembly connector.*3
    6. Disconnect the G59 navigation ECU connector.*4
    7. Disconnect the G55 radio and display receiver assembly connector.
    8. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      F14-17 (+S) - Body ground Always 10 kΩ or higher
      1. *1: w/ Smart Key System
      2. *2: w/ Voltage Inverter
      3. *3: w/ Stereo Component Amplifier Assembly
      4. *4: w/ Navigation System

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  6

  6. CHECK VEHICLE TYPE 
    1. Check vehicle condition.
      RESULT

      Result Proceed to
      w/ Smart Key System A
      w/o Smart Key System B

    Result: 

    B 

    See step  8

    Result: 

    A 

    See step  7

  7. CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) (SHORT CIRCUIT IN CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)) 
    1. Disconnect the F14 combination meter assembly connector.
    2. Disconnect the F113 certification ECU (smart key ECU assembly) connector.
    3. Measure the voltage according to the value(s) in the table below.
      GTY891803Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Combination Meter Assembly)

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      F14-17 (+S) - Body ground Ignition switch ON 11 to 14 V

      HINT: 

      If the result is as specified, there may be a short circuit in the certification ECU (smart key ECU assembly).

    Result: 

    A 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [08/2019 - ] 

    Result: 

    B 

    See step  8

  8. CHECK VEHICLE TYPE 
    1. Check vehicle condition.
      RESULT

      Result Proceed to
      w/ Voltage Inverter A
      w/o Voltage Inverter B

    Result: 

    B 

    See step  10

    Result: 

    A 

    See step  9

  9. CHECK VOLTAGE INVERTER ASSEMBLY (SHORT CIRCUIT IN VOLTAGE INVERTER ASSEMBLY) 
    1. Disconnect the F14 combination meter assembly connector.
    2. Disconnect the N19 voltage inverter assembly connector.
    3. Measure the voltage according to the value(s) in the table below.
      GTY891803Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Combination Meter Assembly)

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      F14-17 (+S) - Body ground Ignition switch ON 11 to 14 V

      HINT: 

      If the result is as specified, there may be a short circuit in the voltage inverter assembly.

    Result: 

    A 

    REPLACE VOLTAGE INVERTER ASSEMBLY. Refer to  REMOVAL [08/2015 - ] 

    Result: 

    B 

    See step  10

  10. CHECK VEHICLE TYPE 
    1. Check vehicle condition.
      RESULT

      Result Proceed to
      w/ Stereo Component Amplifier Assembly A
      w/o Stereo Component Amplifier Assembly B

    Result: 

    B 

    See step  12

    Result: 

    A 

    See step  11

  11. CHECK STEREO COMPONENT AMPLIFIER ASSEMBLY (SHORT CIRCUIT IN STEREO COMPONENT AMPLIFIER ASSEMBLY) 
    1. Disconnect the F14 combination meter assembly connector.
    2. Disconnect the N25 stereo component amplifier assembly connector.
    3. Measure the voltage according to the value(s) in the table below.
      GTY891803Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Combination Meter Assembly)

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      F14-17 (+S) - Body ground Ignition switch ON 11 to 14 V

      HINT: 

      If the result is as specified, there may be a short circuit in the stereo component amplifier assembly.

    Result: 

    A 

    REPLACE STEREO COMPONENT AMPLIFIER ASSEMBLY. Refer to  REMOVAL [08/2015 - ] 

    Result: 

    B 

    See step  12

  12. CHECK VEHICLE TYPE 
    1. Check vehicle condition.
      RESULT

      Result Proceed to
      w/ Navigation System A
      w/o Navigation System B

    Result: 

    B 

    See step  14

    Result: 

    A 

    See step  13

  13. CHECK NAVIGATION ECU (SHORT CIRCUIT IN NAVIGATION ECU) 
    1. Disconnect the F14 combination meter assembly connector.
    2. Disconnect the G59 navigation ECU connector.
    3. Measure the voltage according to the value(s) in the table below.
      GTY891803Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Combination Meter Assembly)

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      F14-17 (+S) - Body ground Ignition switch ON 11 to 14 V

      HINT: 

      If the result is as specified, there may be a short circuit in the navigation ECU.

    Result: 

    OK 

    REPLACE NAVIGATION ECU. Refer to  REMOVAL [08/2019 - ] 

    Result: 

    NG 

    See step  14

  14. CHECK RADIO AND DISPLAY RECEIVER ASSEMBLY (SHORT CIRCUIT IN RADIO AND DISPLAY RECEIVER ASSEMBLY) 
    1. Disconnect the F14 combination meter assembly connector.
    2. Disconnect the G55 radio and display receiver assembly connector.
    3. Measure the voltage according to the value(s) in the table below.
      GTY891803Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Combination Meter Assembly)

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      F14-17 (+S) - Body ground Ignition switch ON 11 to 14 V

      HINT: 

      If the result is as specified, there may be a short circuit in the radio and display receiver assembly.

    Result: 

    OK 

    REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY. Refer to  REMOVAL [08/2019 - ] 

    Result: 

    NG 

    REPLACE ECM. Refer to  REMOVAL [08/2015 - ] 

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