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Stereo Component Amplifier Communication Error

WARNING: This page is about a different car, the 2006 Lexus RX 400h. However, it is still accessible from the selected car via links, so may be relevant.
  1. IDENTIFY THE COMPONENT SHOWN BY THE SUB-CODE 
    1. Enter the diagnostic mode.
      Fig 1: Stereo Component Amplifier Communication Error Diagnostic Flow Chart
      G04115498Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Press the preset switch "3" to change to "Detailed Information Mode".
    3. Identify the component shown by the sub-code.

      HINT:

      • "190 (radio receiver)" is the component shown by the sub-code in the example shown in the illustration.
      • For details of the DTC display, refer to DTC CHECK / CLEAR  .
  2. CHECK POWER SOURCE CIRCUIT OF COMPONENT SHOWN BY SUB-CODE 
    1. Inspect the power source circuit of the component shown by the sub-code.

      If the power source circuit is operating normally, proceed to the next step.

      Component Table 

      COMPONENT REFERENCE TABLE

      Component Proceed to
      Gateway ECU (1C6) GATEWAY ECU POWER SOURCE CIRCUIT 
      Multi-display controller (1F6) MULTI-DISPLAY CONTROLLER POWER SOURCE CIRCUIT 
      Radio receiver (190) RADIO RECEIVER POWER SOURCE CIRCUIT 
  3. INSPECT RADIO RECEIVER 
    1. Disconnect the radio receiver connector.
    2. Measure the resistance according to the value(s) in the table below.

      Resistance 

      RESISTANCE SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      ATX+(R2-5) - ATX-(R2-15) Always 60 to 80 Ω
      TX+(R3-9) - TX-(R3-10) Always 60 to 80 Ω
      TX+(R4-9) - TX-(R4-10) Always 60 to 80 Ω
      Fig 2: Identifying Radio Receiver Connector Terminals
      G04115499Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE RADIO RECEIVER 

    OK: Go to next step. 

  4. CHECK HARNESS AND CONNECTOR (STEREO COMPONENT AMPLIFIER - COMPONENT SHOWN BY SUB-CODE) 

    HINT:

    • Start the check from the circuit that is near the component shown by the sub-code first.
    • For details of the connectors, refer to TERMINALS OF ECU  .
    1. Referring to the AVC-LAN wiring diagram below, check the AVC-LAN circuit between the stereo component amplifier and the component shown by the sub-code.
      1. Check for an open or short in the AVC-LAN circuit between the stereo component amplifier and the component shown by the sub-code.

        OK: There is no open or short circuit. 

        Fig 3: AVC-LAN Wiring Diagram
        G04115500Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step. 

  5. REPLACE COMPONENT SHOWN BY SUB-CODE 
    1. Replace the component shown by the sub-code with a normal one and check if the same problem occurs again.

      OK: Same problem does not occur. 

    NG: REPLACE STEREO COMPONENT AMPLIFIER (STANDARD SYSTEM) 

    NG: REPLACE STEREO COMPONENT AMPLIFIER (MARK LEVINSON SYSTEM) 

    OK: END 

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