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Section 911 (Audio System - Diagnostics): Pre-Check

WARNING: This page is about a different car, the 2005 Toyota 4Runner. However, it is still accessible from the selected car via links, so may be relevant.
  1. DIAGNOSIS CHECK 
    Fig 1: Front View Of Audio System
    G02577394Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Starting Diagnosis Mode (All elements are lighting and in SW check mode).
      1. Turn off the audio system and turn the IG switch to ACC. While pressing the preset switches "1" and "6" at the same time, press "DISC" 3 times.
      2. Reference:
        • Beep sound is given 3 times and the system enters the all elements are lighting and in SW check mode.
        • It may take about 40 sec. to complete the check.
        • Turn all the elements in the LCD on.
        • Make a sound of beeps when pressing the switch.
        • "SEEK TRACK" button switches to "Service Check Screen".
    2. Service Check Screen.
      1. Reference
        • In the service check mode, the system check and the diagnosis memory check are performed, and the check results are displayed in ascending order of the device codes (physical address.)
          COMPONENT CODE REFERENCE

          Terms Meaning
          Component code (Physical address) Three-digit code (In hexadecimal) given to each device comprising AVC-LAN. Corresponding to its function, individual symbol is provided.
          Logical address Two-digit code (In hexadecimal) given to each function and device unit in each device comprising AVC-LAN.

          Code No. (physical address) List 

          CODE NO. (PHYSICAL ADDRESS) LIST

          Code No. (physical address) Equipment name
          190/160 Radio receiver assy (Audio head unit)
          440 Stereo component amplifier
    3. Finishing Diagnosis Mode.
      1. Press "DISC" for 2 sec, or more, or turn the IG switch OFF.
    4. Service Check Mode Result Display (for checking the current and the past system conditions).
      1. Press the "SEEK TRACK" switch to see the check result of each device.
        Fig 2: Identifying Service Check Mode Result Display
        G02577395Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Check Result Display.
        ORIGINAL LANGUAGE DESCRIPTION

        Display Original Language Meaning Action to be taken
        good Good (normal) No DTC is detected in both "System Check Mode" and "Diagnosis Memory Mode". -
        nCon No connection The system recognized the component when it was registered, but the component gives no response to the "Diagnosis Mode ON Request". Check the power source circuit and the communication circuit of the device indicated by the device code (physical address).
        ECHn Exchange One or more DTC for "Exchange" is detected in either "System Check Mode" or "Diagnosis Memory Mode". Go to the detail information mode to check the trouble area referring to the DTC list.
        CHEC Check When no DTC is detected for "Exchange", one or more DTC for "Check" is detected in either "System Check Mode" or "Diagnosis Memory Mode". Go to the detail information mode to check the trouble area referring to the DTC list.
        Old Old version Old DTC application is identified and DTC is detected in either "System Check Mode" or "Diagnosis Memory Mode". -
        nrES No response The device gives no response to any one of "System Check Mode ON Request", "System Check Result Request" and "Diagnosis Memory Request". Check the power source circuit and the communication circuit of the device indicated by the device code (physical code).
      3. To perform the Service Check again, press the preset switch "1".
    5. Detail information Mode (when displaying the troubled device's DTC)
      1. With "CHEC" or "ECHn" being display, press the preset switch "2" to go to the detail information mode.
      2. Press the "TUNE" switch to display "System Check Result (SyS)" and "Diagnosis Memory Response (COdE)".
        Fig 3: Identifying Service Check Mode Display
        G02577396Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. Displayed Items in Detail Information Mode
        Fig 4: Diagnostic Chart
        G02577397Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      4. Check the trouble area referring to the DTC list.
      5. To return to the service check mode, press the preset switch "3".
    6. Clearing Individual DTC Memory (when clearing the memory of DTC detected in the past individually)
      1. Press the preset switch "5" for 2 sec. or more while the "ECHn" is displayed in the service check mode or during the detail information mode.

      HINT:

      • Beep sound is given once when the DTC memory is completely cleared.
      • When DTC memory is cleared, only the component code (physical address) is displayed for the target component.
      • To check DTC, press the preset switch "1" and perform the service check again.
    7. Clearing all DTC memory (when clearing all the memory of DTC detected in the past)
      1. Start the diagnosis mode after repairing the trouble area.
      2. Press the preset switch "5" for 2 sec. or more. ("CLr" is displayed at this time.)

        HINT:

        • Beep sound is given once when the DTC memory is completely cleared.
        • When DTC memory for all the device is cleared, only the component codes (physical address) are displayed.
      3. Press the preset switch "1" to perform the service check again, and check that no DTC is displayed for all the component codes (physical address).
  2. IDENTIFICATION OF NOISE SOURCE 
    1. Identify the condition under which the noise occurs, and check the noise filter on the related part.
      IDENTIFICATION NOISE SOURCE

      Condition in which noise occurs Noise Source
      Depressing the acceleration pedal increases noise, and stopping the engine erases the noise immediately. Generator
      Noise occurs during the A/C or the heater operation. Blower motor
      Rapid acceleration during driving on the unpaved road or after the IG switch is turned ON makes noise. Fuel pump
      Pressing and then releasing the horn switch, and keeping pressing the horn switch makes unusual noise. Horn
      Stopping the engine erases small noise that has been heard. Ignition
      Noise occurs synchronously with the turn signal flash. Flasher
      Noise occurs during the window washer operation. Washer
      Noise occurs during the engine running, and it continues after the engine is stopped. Engine coolant temperature sensor
      Noise occurs during the wiper operation. Wiper
      Noise occurs when the brake pedal is depressed. Stop light switch
      Others. Static electricity stored on the vehicle.
    2. Reference:
      • Make sure first that there is no noise from outside. Failing to do so makes the noise source detection difficult and leads to misunderstanding.
      • The noise should be removed in descending order of loudness.
      • Tuning the radio so that no station is received makes noise noticeable, making the recognition of the phenomenon easier.
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