AUDIO AND VISUAL SYSTEM(for Radio and Display Type) Vehicle Speed Signal Circuit between Radio Receiver and Combination Meter

DTC Code DTC Name
Vehicle Speed Signal Circuit between Radio Receiver and Combination Meter

DESCRIPTION

  • for Automatic Sound Levelizer (ASL):

  • This circuit is necessary for the Automatic Sound Levelizer (ASL) built into the radio and display receiver assembly.

    The Automatic Sound Levelizer (ASL) function automatically adjusts the audio system volume level in order to compensate for increased vehicle noise (vehicle noise tends to increase as vehicle speed increases). The ASL adjusts the volume level based upon vehicle speed signals sent from the combination meter assembly.

  • for "Bluetooth":

  • Vehicle speed signals are received from the combination meter assembly and used to cancel "Bluetooth" function operation.

    The radio and display receiver assembly recognizes that the vehicle is being driven and makes it impossible to connect or register a "Bluetooth" device while driving.

Tip:

  • A voltage of 12 V or 5 V is output from each ECU and then input to the combination meter assembly. The signal is changed to a pulse signal at the transistor in the combination meter assembly. Each ECU controls its respective system based on this pulse signal.

  • If a short occurs in any of the ECUs or in the wire harness connected to an ECU, all systems in the following diagram will not operate normally.

WIRING DIAGRAM

  1. E292674E03

PROCEDURE

  1. CHECK VEHICLE SIGNAL (OPERATION CHECK)

    1. E292315

      Enter the "Vehicle Signal Check Mode" screen. Refer to Check Vehicle Signal Check Mode in Operation Check.

      Click here

    2. While driving the vehicle, compare the value displayed for "SPEED" to the reading on the speedometer. Check if these readings are almost equal.

      Tip:

      The combination meter assembly receives the vehicle speed signal from the skid control ECU via CAN communication. Therefore, perform the following inspection referring to values on the Data List of the skid control ECU because it is the source of the vehicle speed signal.

      OK

      Vehicle speed displayed on the "Vehicle Signal Check Mode" screen is almost the same as the actual vehicle speed measured using the GTS.

      Click here

    Result

    Proceed to

    OK

    NG
    OK

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

    Click here

    NG

  2. INSPECT COMBINATION METER ASSEMBLY (OUTPUT WAVEFORM)

    1. E256135C15

      *a

      Component with harness connected

      (Combination Meter Assembly)

      Check the output waveform.

      1. Remove the combination meter assembly with the connector still connected.

      2. Connect an oscilloscope to terminal E12-22 (+S) and body ground.

      3. Turn the ignition switch to ON.

      4. Turn a wheel slowly.

      5. Check the signal waveform according to the condition(s) in the table below.

        Item

        Condition

        Measurement terminal

        E12-22 (+S) - Body ground

        Tool setting

        5 V/DIV., 20 ms./DIV.

        Vehicle condition

        Wheel being rotated

        OK

        The waveform is similar to that shown in the illustration.

        Tip:

        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

    Proceed to

    OK

    NG
    NG

    GO TO METER / GAUGE SYSTEM

    Click here

    Click here

    OK

  3. INSPECT RADIO AND DISPLAY RECEIVER ASSEMBLY (INPUT WAVEFORM)

    1. E277606C16

      *a

      Component with harness connected

      (Radio and Display Receiver Assembly)

      Check the input waveform.

      1. Remove the radio and display receiver assembly with the connector still connected.

      2. Connect an oscilloscope to terminal E32-16 (SPD) and body ground.

      3. Turn the ignition switch to ON.

      4. Turn a wheel slowly.

      5. Check the signal waveform according to the condition(s) in the table below.

        Item

        Condition

        Measurement terminal

        E32-16 (SPD) - Body ground

        Tool setting

        5 V/DIV., 20 ms./DIV.

        Vehicle condition

        Wheel being rotated

        OK

        The waveform is similar to that shown in the illustration.

        Tip:

        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 (w/ Entry and Start System)

    B

    NG (w/o Entry and Start System)

    C
    A

    REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY

    Click here

    C

    REPAIR OR REPLACE HARNESS OR CONNECTOR (RADIO AND DISPLAY RECEIVER ASSEMBLY - COMBINATION METER ASSEMBLY)

    B

  4. CHECK HARNESS AND CONNECTOR (RADIO AND DISPLAY RECEIVER ASSEMBLY - NO. 5 JUNCTION CONNECTOR)

    1. Disconnect the E32 radio and display receiver assembly connector.

    2. Disconnect the E22 No. 5 junction connector.

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      E32-16 (SPD) - E22-7

      Always

      Below 1 Ω

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

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

    1. Disconnect the E12 combination meter assembly connector.

    2. Disconnect the E22 No. 5 junction connector.

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      E12-22 (+S) - E22-5

      Always

      Below 1 Ω

    Result

    Proceed to

    OK

    NG
    OK

    REPLACE NO. 5 JUNCTION CONNECTOR

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR