METER / GAUGE SYSTEM Speed Signal Circuit

DESCRIPTION

The vehicle speed signal consists of pulses sent to the combination meter assembly from the skid control ECU.

WIRING DIAGRAM

A01IOIEE01
A01IU1DE02

INSPECTION PROCEDURE

PROCEDURE


  1. CHECK ECU TERMINAL VOLTAGE (INPUT VOLTAGE)


    1. A01ISWEE04
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Combination Meter Assembly)

      Disconnect the H62 meter connector.

    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      H62-3 (+S) - Body ground Ignition switch ON 4.5 to 14 V

    NG

    CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - NO. 3 JUNCTION BLOCK) Click here

    OK

  2. CHECK COMBINATION METER ASSEMBLY (OUTPUT VOLTAGE)

    A01INJTE02
    Text in Illustration
    *1 for AD Series Engine
    *2 for ZR Series Engine
    *3

    Front view of wire harness connector

    (to Brake Actuator Assembly)
    *4

    Front view of wire harness connector

    (to Brake Actuator Assembly)

    1. Disconnect the A52*1 or A54*2 brake actuator connector.


      • *1: for AD Series Engine

      • *2: for ZR Series Engine

    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      for AD Series Engine
      Tester Connection Switch Condition Specified Condition
      A52-33 (SP1) - Body ground Ignition switch ON 11 to 14 V
      for ZR Series Engine
      Tester Connection Switch Condition Specified Condition
      A54-33 (SP1) - Body ground Ignition switch ON 11 to 14 V

    NG

    CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - BRAKE ACTUATOR ASSEMBLY) Click here

    OK

  3. CHECK COMBINATION METER ASSEMBLY (SPEED SIGNAL)


    1. A01IPMME01

      Check the input waveform.


      1. Reconnect the H62 meter connector.

      2. Remove the combination meter assembly with the connector(s) still connected.

      3. Connect an oscilloscope to terminal H62-5 (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) H62-5 (SI) - Body ground
        Tool setting 5 V/DIV., 20 ms./DIV.
        Condition Being driven at approximately 20 km/h (12 mph)
        OK
        The waveform displayed is as shown in the illustration.

        Tech Tips

        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

    REPLACE BRAKE ACTUATOR ASSEMBLY Click here

    OK

    REPLACE COMBINATION METER ASSEMBLY Click here

  4. CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - BRAKE ACTUATOR ASSEMBLY)

    A01IN9ME02
    Text in Illustration
    *1 for AD Series Engine
    *2 for ZR Series Engine
    *3

    Front view of wire harness connector

    (to Combination Meter Assembly)
    *4

    Front view of wire harness connector

    (to Brake Actuator Assembly)
    *5

    Front view of wire harness connector

    (to Brake Actuator Assembly)

    1. Disconnect the H62 meter connector.

    2. Disconnect the A52*1 or A54*2 brake actuator connector.


      • *1: for AD Series Engine

      • *2: for ZR Series Engine

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      for AD Series Engine
      Tester Connection Condition Specified Condition
      H62-5 (SI) - A52-33 (SP1) Always Below 1 Ω
      A52-33 (SP1) - Body ground Always 10 kΩ or higher
      for ZR Series Engine
      Tester Connection Condition Specified Condition
      H62-5 (SI) - A54-33 (SP1) Always Below 1 Ω
      A54-33 (SP1) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE COMBINATION METER ASSEMBLY Click here

  5. CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - NO. 3 JUNCTION BLOCK)


    1. Disconnect the H62 meter connector.

      A01IUIOE01
      Text in Illustration
      *1

      Front view of wire harness connector

      (to No. 3 Junction Block)

      		 *2

      Front view of wire harness connector

      (to Combination Meter Assembly)

    2. Disconnect the 3A junction block connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      H62-3 (+S) - 3A-55 Always Below 1 Ω
      H62-3 (+S) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. CHECK POWER MANAGEMENT CONTROL ECU

    Note

    For vehicles with neither the entry and start system nor the TOYOTA parking assist-sensor system, go to "Check Radio Receiver Assembly".


    1. Disconnect the 3B junction block connector.

      A01IT76E02
      Text in Illustration
      *1

      Front view of wire harness connector

      (to No. 3 Junction Block)

      		 - -

    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      3B-67 - Body ground Ignition switch ON 4.5 to 14 V

    NG

    CHECK HARNESS AND CONNECTOR (NO. 3 JUNCTION BLOCK - NO. 4 JUNCTION BLOCK) Click here

    OK

  7. CHECK RADIO RECEIVER ASSEMBLY

    Note

    For vehicles radio and display type, go to "Check Radio and Display Receiver Assembly".


    1. Disconnect the 3A junction block connector.

      A01IUH4E04
      Text in Illustration
      *1

      Front view of wire harness connector

      (to No. 3 Junction Block)

      		 - -

    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      3A-43 - Body ground Ignition switch ON 4.5 to 14 V

    NG

    CHECK HARNESS AND CONNECTOR (RADIO RECEIVER ASSEMBLY CIRCUIT) Click here

    OK

  8. CHECK RADIO AND DISPLAY RECEIVER ASSEMBLY

    Note

    For vehicles radio receiver type, go to "Check Headlight Leveling ECU".


    1. Disconnect the 3A junction block connector.

      A01IUH4E04
      Text in Illustration
      *1

      Front view of wire harness connector

      (to No. 3 Junction Block)

      		 - -

    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      3A-43 - Body ground Ignition switch ON 4.5 to 14 V

    NG

    CHECK HARNESS AND CONNECTOR (RADIO AND DISPLAY RECEIVER ASSEMBLY CIRCUIT) Click here

    OK

  9. CHECK HEADLIGHT LEVELING ECU ASSEMBLY

    Note

    For vehicles without an HID headlight system, go to "Check TCM".


    1. Disconnect the 3A junction block connector.

      A01IUH4E05
      Text in Illustration
      *1

      Front view of wire harness connector

      (to No. 3 Junction Block)

      		 - -

    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      3A-19 - Body ground Ignition switch ON 4.5 to 14 V

    NG

    CHECK HARNESS AND CONNECTOR (HEADLIGHT LEVELING ECU ASSEMBLY CIRCUIT) Click here

    OK

  10. CHECK TCM

    Note

    For vehicles with a manual transaxle or CVT, go to "Check ECM".


    1. Disconnect the 3A junction block connector.

      A01IUH4E12
      Text in Illustration
      *1

      Front view of wire harness connector

      (to No. 3 Junction Block)

      		 - -

    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      3A-54 - Body ground Ignition switch ON 4.5 to 14 V

    NG

    CHECK HARNESS AND CONNECTOR (TCM CIRCUIT) Click here

    OK

  11. CHECK ECM


    1. Disconnect the 3A junction block connector.

      A01IUH4E03
      Text in Illustration
      *1

      Front view of wire harness connector

      (to No. 3 Junction Block)

      		 - -

    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      3A-20 - Body ground Ignition switch ON 4.5 to 14 V

    NG

    CHECK HARNESS AND CONNECTOR (ECM CIRCUIT) Click here

    OK

    REPLACE NO. 3 JUNCTION BLOCK

  12. CHECK HARNESS AND CONNECTOR (NO. 3 JUNCTION BLOCK - NO. 4 JUNCTION BLOCK)


    1. Disconnect the 3B junction block connector.

      A01IRW0E01
      Text in Illustration
      *1

      Front view of wire harness connector

      (to No. 3 Junction Block)

      		 *2

      Front view of wire harness connector

      (to No. 4 Junction Block)

    2. Disconnect the 4A junction block connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      3B-67 - 4A-61 Always Below 1 Ω
      3B-67 - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  13. CHECK NO. 4 JUNCTION BLOCK


    1. Disconnect the 4A junction block connector.

      A01IOROE03
      Text in Illustration
      *1

      Front view of wire harness connector

      (to No. 4 Junction Block)

      		 - -

    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      4A-85 - Body ground Ignition switch ON 4.5 to 14 V
      4A-13 - Body ground Ignition switch ON 4.5 to 14 V
      Result
      Result Proceed to
      NG (4A-85) A
      NG (4A-13) B
      OK C

    B

    CHECK HARNESS AND CONNECTOR (CLEARANCE WARNING ECU CIRCUIT) Click here

    C

    REPLACE NO. 4 JUNCTION BLOCK

    A

  14. CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU CIRCUIT)


    1. Disconnect the 4A junction block connector.

      A01INNQE01
      Text in Illustration
      *1

      Front view of wire harness connector

      (to No. 4 Junction Block)

      		 *2

      Front view of wire harness connector

      (to Power Management Control ECU)

    2. Disconnect the H71 power management control ECU connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      H71-23 (SPD) - 4A-85 Always Below 1 Ω
      4A-85 - Body ground Always 10 kΩ or higher
      Result
      Result Proceed to
      OK (for LHD) A
      OK (for RHD) B
      NG C

    B

    REPLACE POWER MANAGEMENT CONTROL ECU Click here

    C

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    A

    REPLACE POWER MANAGEMENT CONTROL ECU Click here

  15. CHECK HARNESS AND CONNECTOR (RADIO RECEIVER ASSEMBLY CIRCUIT)


    1. Disconnect the 3A junction block connector.

      A01INJ1E01
      Text in Illustration
      *1

      Front view of wire harness connector

      (to No. 3 Junction Block)

      		 *2

      Front view of wire harness connector

      (to Radio Receiver Assembly)

    2. Disconnect the H114 radio receiver connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      H114-17 (SPD) - 3A-43 Always Below 1 Ω
      3A-43 - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE RADIO RECEIVER ASSEMBLY Click here

  16. CHECK HARNESS AND CONNECTOR (RADIO AND DISPLAY RECEIVER ASSEMBLY CIRCUIT)


    1. Disconnect the 3A junction block connector.

      A01INJ1E02
      Text in Illustration
      *1

      Front view of wire harness connector

      (to No. 3 Junction Block)

      		 *2

      Front view of wire harness connector

      (to Radio and Display Receiver Assembly)

    2. Disconnect the H105 radio and display receiver connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      H105-17 (SPD) - 3A-43 Always Below 1 Ω
      3A-43 - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY Click here

  17. CHECK HARNESS AND CONNECTOR (HEADLIGHT LEVELING ECU ASSEMBLY CIRCUIT)


    1. Disconnect the 3A junction block connector.

      A01IRLIE01
      Text in Illustration
      *1

      Front view of wire harness connector

      (to No. 3 Junction Block)

      		 *2

      Front view of wire harness connector

      (to Headlight Leveling ECU)

    2. Disconnect the A49 headlight leveling ECU connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      A49-16 (SPDR) - 3A-19 Always Below 1 Ω
      3A-19 - Body ground Always 10 kΩ or higher
      Result
      Result Proceed to
      OK (for LHD) A
      OK (for RHD) B
      NG C

    B

    REPLACE HEADLIGHT LEVELING ECU ASSEMBLY Click here

    C

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    A

    REPLACE HEADLIGHT LEVELING ECU ASSEMBLY Click here

  18. CHECK HARNESS AND CONNECTOR (TCM CIRCUIT)


    1. Disconnect the 3A junction block connector.

      A01IOBNE03
      Text in Illustration
      *1

      Front view of wire harness connector

      (to No. 3 Junction Block)

      		 *2

      Front view of wire harness connector

      (to TCM)

    2. Disconnect the C29 TCM connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      C29-3 (SPD) - 3A-54 Always Below 1 Ω
      3A-54 - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE TCM Click here

  19. CHECK HARNESS AND CONNECTOR (ECM CIRCUIT)


    1. Disconnect the 3A junction block connector.

      A01IOH8E01
      Text in Illustration
      *1

      Front view of wire harness connector

      (to No. 3 Junction Block)

      		 *2

      Front view of wire harness connector

      (to ECM)
      *3 for AD Series Engine *4 for ZR Series Engine

    2. Disconnect the A51 ECM connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      for AD Series Engine
      Tester Connection Condition Specified Condition
      A51-14 (SPD) - 3A-20 Always Below 1 Ω
      3A-20 - Body ground Always 10 kΩ or higher
      for ZR Series Engine
      Tester Connection Condition Specified Condition
      A51-38 (SPD) - 3A-20 Always Below 1 Ω
      3A-20 - Body ground Always 10 kΩ or higher
      Result
      Result Proceed to
      NG A
      OK (for 1ZR-FAE) B
      OK (for 2ZR-FAE) C
      OK (for 1AD-FTV) D
      OK (for 2AD-FHV) E

    B

    REPLACE ECM Click here

    C

    REPLACE ECM Click here

    D

    REPLACE ECM Click here

    E

    REPLACE ECM Click here

    A

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  20. CHECK HARNESS AND CONNECTOR (CLEARANCE WARNING ECU CIRCUIT)


    1. Disconnect the 4A junction block connector.

      A01IO5GE01
      Text in Illustration
      *1

      Front view of wire harness connector

      (to No. 4 Junction Block)

      		 *2

      Front view of wire harness connector

      (to Clearance Warning ECU)

    2. Disconnect the H95 clearance warning ECU connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      H95-5 (SPD) - 4A-13 Always Below 1 Ω
      4A-13 - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE CLEARANCE WARNING ECU ASSEMBLY Click here