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Inspection Procedure

  1. CHECK HARNESS AND CONNECTOR 
    1. Disconnect the connectors shown in the illustration from the stereo component amplifier and speakers.
    2. with Front Center Speaker:

      Measure the resistance between the front stereo component speaker and the stereo component amplifier to check for an open circuit in the wire harness.

      Standard resistance: 

      Below 1 Ω 

    3. Measure the resistance between each of the front No. 3 speakers and the stereo component amplifier to check for an open circuit in the wire harness.

      Standard resistance: 

      Below 1 Ω 

    4. Measure the resistance between each of the front No. 2 speakers and the front No. 3 speakers to check for an open circuit in the wire harness.

      Standard resistance: 

      Below 1 Ω 

    5. without Front Center Speaker:

      Measure the resistance between each of the rear speakers and the stereo component amplifier to check for an open circuit in the wire harness.

      Standard resistance: 

      Below 1 Ω 

    6. with Front Center Speaker:

      Measure the resistance between each of the rear speakers and the stereo component amplifier to check for an open circuit in the wire harness.

      Standard resistance: 

      Below 1 Ω 

    7. without Front Center Speaker:

      Measure the resistance between each of the rear No. 3 speakers and the stereo component amplifier to check for an open circuit in the wire harness.

      Standard resistance: 

      Below 1 Ω 

      Fig 1: Identifying Stereo Component Amplifier Connector Terminal And Speakers Connector Terminal
      G05828171Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    8. without Front Center Speaker:

      Measure the resistance between each of the rear No. 2 speakers and the rear No. 3 speakers to check for an open circuit in the wire harness.

      Standard resistance: 

      Below 1 Ω 

    9. with Front Center Speaker:

      Measure the resistance between each of the rear No. 2 speakers and the rear speakers to check for an open circuit in the wire harness.

      Standard resistance: 

      Below 1 Ω 

    10. with Front Center Speaker:

      Measure the resistance between each of the rear stereo component speakers and the stereo component amplifier to check for an open circuit in the wire harness.

      Standard resistance: 

      Below 1 Ω 

    11. Measure the resistance between each of the front No. 1 speakers and the stereo component amplifier to check for an open circuit in the wire harness.

      Standard resistance: 

      Below 1 Ω 

    12. Measure the resistance between the woofer box speaker and the stereo component amplifier to check for an open circuit in the wire harness.

      Standard resistance: 

      Below 1 Ω 

    13. Measure the resistance between each speaker and body ground to check for a short circuit in the wire harness.

      Standard resistance: 

      10 kΩ or higher 

      Fig 2: Identifying Stereo Component Connector Terminal
      G05828172Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  2. INSPECT FRONT NO. 1 SPEAKER 
    1. Resistance check.
      1. Measure the resistance between the terminals of the speaker.

        Standard resistance: 

        with Front Center Speaker: 

        6 to 10 Ω 

        without Front Center Speaker: 

        Approximately 4 Ω 

        HINT:

        Perform the above inspection on both LH and RH sides.

    NG: REPLACE FRONT NO. 1 SPEAKER 

    OK: Go to next step 

  3. INSPECT FRONT NO. 2 SPEAKER 
    1. Check that the malfunction disappears when another speaker in good condition is installed.

      Standard: 

      Malfunction disappears. 

      HINT:

      • Connect all the connectors to the front No. 2 speakers.
      • When there is a possibility that either the right or left front speaker is detective, inspect by interchanging the right one with the left one.
      • Perform the above inspection on both LH and RH sides.

    OK: REPLACE FRONT NO. 2 SPEAKER 

    NG: Go to next step 

  4. INSPECT FRONT NO. 3 SPEAKER 
    1. Check that the malfunction disappears when another speaker in good condition is installed.

      Standard: 

      Malfunction disappears. 

      HINT:

      • Connect all the connectors to the front speakers.
      • When there is a possibility that either the right or left front speaker is defective, inspect by interchanging the right one with the left one.
      • Perform the above inspection on both LH and RH sides.

    OK: REPLACE FRONT NO. 3 SPEAKER 

    NG: Go to next step 

  5. INSPECT REAR NO. 2 SPEAKER 
    1. Check that the malfunction disappears when another speaker in good condition is installed.

      Standard: 

      Malfunction disappears. 

      HINT:

      • Connect all the connectors to the rear No. 2 speakers.
      • When there is a possibility that either the right or left rear speaker is detective, inspect by interchanging the right one with the left one.
      • Perform the above inspection on both LH and RH sides.

    OK: REPLACE REAR NO. 2 SPEAKER 

    NG: Go to next step 

  6. CONFIRM MODEL 

    Result 

    RESULT REFERENCE

    Result Proceed to
    with Front Center Speaker A
    without Front Center Speaker B

    B: Go to step   11 

    A: Go to next step 

  7. INSPECT REAR SPEAKER 
    1. Check that the malfunction disappears when another speaker in good condition is installed.

      Standard: 

      Malfunction disappears. 

      HINT:

      • Connect all the connectors to the rear speakers.
      • When there is a possibility that either the right or left rear speaker is detective, inspect by interchanging the right one with the left one.
      • Perform the above inspection on both LH and RH sides.

    OK: REPLACE REAR SPEAKER 

    NG: Go to next step 

  8. INSPECT REAR STEREO COMPONENT SPEAKER 
    1. Check that the malfunction disappears when another speaker in good condition is installed.

      OK: 

      Malfunction disappears. 

      HINT:

      • Connect all the connectors to the rear stereo component speakers.
      • When there is a possibility that either the right or left rear speaker is detective, inspect by interchanging the right one with the left one.
      • Perform the above inspection on both LH and RH sides.

    OK: REPLACE REAR STEREO COMPONENT SPEAKER 

    NG: Go to next step 

  9. INSPECT FRONT STEREO COMPONENT SPEAKER 
    1. Resistance check.
      1. Measure the resistance between the terminals of the speaker.

        Standard resistance: 

        7 to 9 Ω 

    NG: REPLACE FRONT STEREO COMPONENT SPEAKER 

    OK: Go to next step 

  10. INSPECT WOOFER BOX SPEAKER 
    1. Resistance check.
      1. Measure the resistance according to the value(s) in the table below.
        NOTE: The speaker should not be removed for checking.
        Fig 3: Identifying Woofer Box Speaker Connector Terminal
        G04966995Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Standard resistance 

        RESISTANCE REFERENCE

        Tester connection Condition Specified condition
        3-4 Always 7 to 8.6 Ω

    NG: REPLACE WOOFER BOX SPEAKER 

    OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN  PROBLEM SYMPTOMS TABLE  

  11. INSPECT REAR NO. 3 SPEAKER 
    1. Check that the malfunction disappears when another speaker in good condition is installed.

      Standard: 

      Malfunction disappears. 

      HINT:

      • Connect all the connectors to the rear No. 3 speakers.
      • When there is a possibility that either the right or left rear No. 3 speaker is detective, inspect by interchanging the right one with the left one.
      • Perform the above inspection of both LH or RH sides.

    OK: REPLACE REAR NO. 3 SPEAKER 

    NG: Go to next step 

  12. INSPECT REAR SPEAKER 
    1. Resistance check.
      1. Measure the resistance according to the value(s) in the table below.

        Standard resistance: 

        Approximately 4 Ω 

        HINT:

        Perform the above inspection on both LH and RH sides.

    NG: REPLACE REAR SPEAKER 

    OK: Go to next step 

  13. INSPECT WOOFER BOX SPEAKER 
    1. Resistance check.
      1. Measure the resistance according to the value(s) in the table below.
        NOTE: The speaker should not be removed for checking.
        Fig 4: Identifying Woofer Box Speaker Connector Terminal
        G04966995Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Standard resistance 

        RESISTANCE REFERENCE

        Tester connection Condition Specified condition
        1-3 Always Approximately 2 Ω
        2-4 Always Approximately 2 Ω

    NG: REPLACE WOOFER BOX SPEAKER 

    OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN  PROBLEM SYMPTOMS TABLE  

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