2003 Lexus SC 430FACTORY OEM SERVICE PROCEDURE

Section 538 (Audio System): Inspection

WARNING: This page is about a different car, the 2004 Lexus LX 470. However, it is still accessible from the selected car via links, so may be relevant.
  1. INSPECT POWER AMPLIFIER CIRCUIT 

    Disconnect the connector from the power amplifier and inspect the connector on the wire harness side.

    Fig 1: Disconnecting Connector From Power Amplifier
    G03486051Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    TESTER CONDITION SPECIFICATION

    Tester connection Condition Specified condition
    12 - Ground Always Continuity
    13 - Ground Always Continuity
    7 - Ground Always Battery voltage
    16 - Ground Always Battery voltage

    If the circuit is not as specified, inspect the circuits connected to other parts.

  2. INSPECT REAR SEAT AUDIO CIRCUIT 

    Disconnect the connector from RSA controller and inspect the connector on the wire harness side.

    Fig 2: Identifying Rear Seat Audio Circuit Connector
    G03486052Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    TESTER CONDITION SPECIFICATION

    Tester connection Condition Specified condition
    17 - Ground Always Continuity
    24 - Ground Ignition switch LOCK and radio switch ON No voltage
    24 - Ground Ignition switch ACC or ON and radio switch ON Battery voltage
    12 - Ground Always Battery voltage

    If the circuit is not as specified, inspect the circuits connected to other parts.

  3. INSPECT DVD CHANGER CIRCUIT 

    Disconnect the connector from the DVD changer and inspect the connector on the wire harness side.

    Fig 3: Identifying DVD Changer Circuit
    G03486053Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    TESTER CONDITION SPECIFICATION

    Tester connection Condition Specified condition
    20 - Ground Always Continuity
    1 - Ground Ignition switch LOCK and radio switch ON No voltage
    1 - Ground Ignition switch ACC or ON and radio switch ON Battery voltage
    10 - Ground Always Battery voltage

    If the circuit is not as specified, inspect the circuits connected to other parts.

  4. INSPECT RADIO RECEIVER ASSEMBLY CIRCUIT 

    Disconnect the connectors from the radio receiver assembly, and inspect the connector on the wire harness side.

    Fig 4: Inspecting Radio Receiver Assembly Connector
    G03486054Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    TESTER CONDITION SPECIFICATION

    Tester connection Condition Specified condition
    A20 - Ground Always Continuity
    A1 - Ground Always Battery voltage
    A11 - Ground Ignition switch LOCK No voltage
    A11 - Ground Ignition switch ACC or ON Battery voltage

    If the circuit is not as specified, inspect the circuits connected to other parts.

    HINT:

    Check the wire harness between the radio receiver assembly and the CD auto changer and between the radio receiver assembly and the power amplifier.

  5. INSPECT STEERING PAD SWITCH CIRCUIT 

    Disconnect the connectors from the steering pad switch, and inspect the connector on the wire harness side.

    Fig 5: Disconnecting Connectors From Steering Pad Switch
    G03486055Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    TESTER CONDITION SPECIFICATION

    Tester connection Condition Specified condition
    AU1 - EAU Do not switch position Approx. 100 kΩ
    AU1 - EAU SEEK+ switch: push 0Ω
    AU1 - EAU SEEK- switch: push Approx. 0.3 Ω
    AU1 - EAU VOL+ switch: push Approx. 1 kΩ
    AU1 - EAU VOL- switch: push Approx. 3.2 kΩ
    AU2 - EAU Do not switch position Approx. 100 kΩ
    AU2 - EAU MODE switch: push 0Ω

    If the circuit is not as specified, inspect the circuits connector to other parts.

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