METER / GAUGE SYSTEM Speed Signal Circuit

DESCRIPTION

The combination meter assembly receives the vehicle speed signal from this circuit. The wheel speed sensors produce an output that varies according to the vehicle speed. The wheel speed sensor output is received by the brake actuator assembly (skid control ECU), which uses this information to create the vehicle speed sensor signal*1. The vehicle speed sensor signal consists of pulses sent to the combination meter assembly from the brake actuator assembly (skid control ECU). To create this signal, 12 V is output from IG2, which is behind a resistor in the combination meter assembly. This voltage is sent to the brake actuator assembly (skid control ECU). The pulse signal is created by switching the transistor in the brake actuator assembly (skid control ECU) on and off, making the voltage on the wire drop to 0 V. A similar system is used for the output of this signal from the combination meter assembly via terminal +S. A voltage of 12 V or 5 V is applied to terminal +S from each ECU or relay that is connected to this terminal. The transistor in the combination meter assembly is controlled by the signal from the brake actuator assembly (skid control ECU). When this transistor is turned on, this transistor makes the voltage supplied by the various ECUs (via their respective internal resistors) drop to 0 V. Each ECU connected to terminal +S of the combination meter assembly controls its respective system based on the pulse signal.


Tech Tips

This circuit is used for the systems connected to terminal +S. This signal is not used for combination meter assembly operation. Combination meter assembly components such as the speedometer operate using data received via CAN communication.

WIRING DIAGRAM

A005KECE02

PROCEDURE


  1. INSPECT COMBINATION METER ASSEMBLY (INPUT VOLTAGE)


    1. A005IS6E01
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Combination Meter Assembly)

      Disconnect the F1 combination meter assembly connector.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      F1-6 (+S) - Body ground Ignition switch ON 4.5 to 14 V

      Tech Tips

      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.

    3. Reconnect the F1 combination meter assembly connector.


    NG
    OK
  2. INSPECT COMBINATION METER ASSEMBLY (OUTPUT VOLTAGE)


    1. A005LPVE02
      Text in Illustration
      *A except LHD with CVT
      *B for LHD with CVT
      *a

      Front view of wire harness connector

      (to Brake Actuator Assembly (Skid Control ECU))

      Disconnect the A54*1 or A56*2 brake actuator assembly (skid control ECU) connector.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      A54-11 (SP1)*1 - Body ground Ignition switch ON 11 to 14 V
      A56-11 (SP1)*2 - Body ground Ignition switch ON 11 to 14 V

      • *1: except LHD with CVT

      • *2: for LHD with CVT

    3. Reconnect the A54*1 or A56*2 brake actuator assembly (skid control ECU) connector.


      • *1: except LHD with CVT

      • *2: for LHD with CVT


    NG
    OK
  3. INSPECT BRAKE ACTUATOR ASSEMBLY (INPUT WAVEFORM)


    1. A005LVNE02
      Text in Illustration
      *a

      Component with harness connected

      (Combination Meter Assembly)

      Check the input waveform.


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

      2. Connect an oscilloscope to terminal F1-5 (SI) and body ground.

      3. Turn the ignition switch to ON.

      4. Turn the wheel slowly.

      5. 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 approximately 20 km/h (12 mph)
        OK
        The waveform is displayed as shown in the illustration.

        Tech Tips

        As the vehicle speed increases, the cycle of the waveform narrows.

        Result
        Result Proceed to
        OK A
        NG (for LHD) B
        NG (for RHD) C

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


    1. Disconnect the F1 combination meter assembly connector.

    2. Disconnect the A54*1 or A56*2 brake actuator assembly (skid control ECU) connector.

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      A54-11 (SP1)*1 - F1-5 (SI) Always Below 1 Ω
      A56-11 (SP1)*2 - F1-5 (SI) Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      A54-11 (SP1)*1 - Body ground Always 10 kΩ or higher
      A56-11 (SP1)*2 - Body ground Always 10 kΩ or higher

      • *1: except LHD with CVT

      • *2: for LHD with CVT


    OK
    NG
  5. CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - INSTRUMENT PANEL JUNCTION BLOCK)


    1. Disconnect the 3B instrument panel junction block assembly connector.

    2. Disconnect the F1 combination meter assembly connector.

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      F1-6 (+S) - 3B-15 Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      F1-6 (+S) - Body ground Always 10 kΩ or higher
    4. Reconnect the 3B instrument panel junction block assembly connector.

    5. Reconnect the F1 combination meter assembly connector.


    NG
    OK
  6. INSPECT ECM


    1. A005M3XE02
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Instrument Panel Junction Block Assembly)

      Disconnect the 3C instrument panel junction block assembly connector.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      3C-39 - Body ground Ignition switch ON 4.5 to 14 V
    3. Reconnect the 3C instrument panel junction block assembly connector.


    NG
    OK
  7. INSPECT HEADLIGHT LEVELING ECU ASSEMBLY

    Tech Tips

    For vehicles without HID headlight, go to "INSPECT WINDSHIELD WIPER RELAY ASSEMBLY".


    1. A005M3XE02
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Instrument Panel Junction Block Assembly)

      Disconnect the 3C instrument panel junction block assembly connector.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      3C-40 - Body ground Ignition switch ON 4.5 to 14 V
    3. Reconnect the 3C instrument panel junction block assembly connector.


    NG
    OK
  8. INSPECT WINDSHIELD WIPER RELAY ASSEMBLY

    Tech Tips

    For vehicles without rain sensor, go to "INSPECT CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)".


    1. A005INVE02
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Instrument Panel Junction Block Assembly)

      Disconnect the 3A instrument panel junction block assembly connector.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      3A-37 - Body ground Ignition switch ON 4.5 to 14 V
    3. Reconnect the 3A instrument panel junction block assembly connector.


    NG
    OK
  9. INSPECT CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

    Tech Tips

    For vehicles without entry and start system, go to "INSPECT RADIO RECEIVER ASSEMBLY OR RADIO AND DISPLAY RECEIVER ASSEMBLY".


    1. A005INVE02
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Instrument Panel Junction Block Assembly)

      Disconnect the 3A instrument panel junction block assembly connector.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      3A-38 - Body ground Ignition switch ON 4.5 to 14 V
    3. Reconnect the 3A instrument panel junction block assembly connector.


    NG
    OK
  10. INSPECT RADIO RECEIVER ASSEMBLY OR RADIO AND DISPLAY RECEIVER ASSEMBLY

    Tech Tips

    For vehicles without audio system, Replace the Instrument panel junction block assembly.


    1. A005INVE02
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Instrument Panel Junction Block Assembly)

      Disconnect the 3A instrument panel junction block assembly connector.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      3A-16 - Body ground Ignition switch ON 4.5 to 14 V
    3. Reconnect the 3A instrument panel junction block assembly connector.


    OK
    NG
  11. CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK - ECM)


    1. Disconnect the 3C instrument panel junction block assembly connector.

    2. Disconnect the A58*1 or A59*2 ECM connector.

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


      • *1: except 1ND-TV

      • *2: for 1ND-TV

      Standard Resistance (Check for Open)
      for 1NR-FE
      Tester Connection Condition Specified Condition
      3C-39 - A58-44 (SPD) Always Below 1 Ω
      for 1NZ-FE
      Tester Connection Condition Specified Condition
      3C-39 - A58-44 (SPD) Always Below 1 Ω
      for 1ND-TV
      Tester Connection Condition Specified Condition
      3C-39 - A59-25 (SPD) Always Below 1 Ω
      Standard Resistance (Check for Short)
      for 1NR-FE
      Tester Connection Condition Specified Condition
      3C-39 - Body ground Always 10 kΩ or higher
      for 1NZ-FE
      Tester Connection Condition Specified Condition
      3C-39 - Body ground Always 10 kΩ or higher
      for 1ND-TV
      Tester Connection Condition Specified Condition
      3C-39 - Body ground Always 10 kΩ or higher
      Result
      Result Proceed to
      NG A
      OK (for 1NR-FE) B
      OK (for 1NZ-FE) C
      OK (for 1ND-TV) D
    4. Reconnect the 3C instrument panel junction block assembly connector.

    5. Reconnect the A58*1 or A59*2 ECM connector.


      • *1: except 1ND-TV

      • *2: for 1ND-TV


    A
    B
    C
    D
  12. CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK - HEADLIGHT LEVELING ECU)


    1. Disconnect the 3C instrument panel junction block assembly connector.

    2. Disconnect the A43 headlight leveling ECU assembly connector.

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      3C-40 - A43-16 (SPDR) Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      3C-40 - Body ground Always 10 kΩ or higher
    4. Reconnect the 3C instrument panel junction block assembly connector.

    5. Reconnect the A43 headlight leveling ECU assembly connector.


    OK
    NG
  13. CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK - WINDSHIELD WIPER RELAY)


    1. Disconnect the 3A instrument panel junction block assembly connector.

    2. Disconnect the F72 windshield wiper relay assembly connector.

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      3A-37 - F72-24 (SPD) Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      3A-37 - Body ground Always 10 kΩ or higher
    4. Reconnect the 3A instrument panel junction block assembly connector.

    5. Reconnect the F72 windshield wiper relay assembly connector.


    OK
    NG
  14. CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK - CERTIFICATION ECU)


    1. Disconnect the 3A instrument panel junction block assembly connector.

    2. Disconnect the F63 certification ECU (smart key ECU assembly) connector.

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      3A-38 - F63-27 (SPD) Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      3A-38 - Body ground Always 10 kΩ or higher
    4. Reconnect the 3A instrument panel junction block assembly connector.

    5. Reconnect the F63 certification ECU (smart key ECU assembly) connector.


    OK
    NG
  15. CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK - RADIO RECEIVER ASSEMBLY OR RADIO AND DISPLAY RECEIVER ASSEMBLY)


    1. Disconnect the 3A instrument panel junction block assembly connector.

    2. Disconnect the F47 radio receiver assembly*1 or radio and display receiver assembly*2 connector.

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      3A-16 - F47-17 (SPD) Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      3A-16 - Body ground Always 10 kΩ or higher
    4. Reconnect the 3A instrument panel junction block assembly connector.

    5. Reconnect theF47 radio receiver assembly*1 or radio and display receiver assembly*2 connector.


      • *1: w/ Radio Receiver Assembly

      • *2: w/ Radio and Display Receiver Assembly


    OK
    NG