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Microphone Circuit between Microphone and Navigation Receiver Assembly: Procedure

  1. CHECK VEHICLE EQUIPMENT 
    1. Check if the telephone switch is equipped on the vehicle.
      RESULT

      Result Proceed to
      w/ Telephone Switch A
      w/o Telephone Switch B

    B → See step   10 

    A: Go to next step 

  2. CHECK NAVIGATION RECEIVER ASSEMBLY 
    1. Measure the resistance according to the value(s) in the table below.
      Fig 1: Identifying Navigation Receiver Connector Terminal Identification
      GTY215473Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Condition Specified Condition
      G20-18 (SGND) - Body ground Always Below 1 Ω
      G20-20 (MIN-) - Body ground Always Below 1 Ω
      TEXT IN ILLUSTRATION

      *a Component with harness connected
      (Navigation Receiver Assembly)

    NG → See step   15 

    OK: Go to next step 

  3. CHECK HARNESS AND CONNECTOR (NAVIGATION RECEIVER - MAP LIGHT) 
    1. Disconnect the G20 navigation receiver assembly connector.
    2. Disconnect the U2 map light assembly connector.
    3. Measure the resistance according to the value(s) in the below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      G20-5 (SNS2) - U2-15 (SNS2) Always Below 1 Ω

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  4. CHECK HARNESS AND CONNECTOR (NAVIGATION RECEIVER - TELEMATICS TRANSCEIVER) 
    1. Disconnect the G20 navigation receiver assembly connector.
    2. Disconnect the F39 telematics transceiver connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      G20-19 (MIN+) - F39-18 (MCO+) Always Below 1 Ω
      G20-20 (MIN-) - F39-19 (MCO-) Always Below 1 Ω
      G20-19 (MIN+) - Body ground Always 10 kΩ or higher
      G20-20 (MIN-) - Body ground Always 10 kΩ or higher
      G20-18 (SGND) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  5. CHECK HARNESS AND CONNECTOR (TELEMATICS TRANSCEIVER - MAP LIGHT) 
    1. Disconnect the F39 telematics transceiver connector.
    2. Disconnect the U2 map light assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      F39-33 (MCVD) - U2-14 (MACC) Always Below 1 Ω
      F39-34 (MCI+) - U2-13 (MCO+) Always Below 1 Ω
      F39-35 (MCI-) - U2-12 (MCO-) Always Below 1 Ω
      F39-33 (MCVD) - Body ground Always 10 kΩ or higher
      F39-34 (MCI+) - Body ground Always 10 kΩ or higher
      F39-35 (MCI-) - Body ground Always 10 kΩ or higher
      F39-32 (SGND) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  6. CHECK TELEMATICS TRANSCEIVER 
    1. Measure the voltage according to the value(s) in the table below.
      Fig 2: Identifying Telematics Transceiver Connector Terminal Identification
      GTY224154Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      F39-33 (MCVD) - Body ground Ignition switch ACC 5 V
      TEXT IN ILLUSTRATION

      *a Component with harness connected
      (Telematics Transceiver)

    NG → See step   17 

    OK: Go to next step 

  7. INSPECT MAP LIGHT ASSEMBLY 
    1. Remove the map light assembly, refer to REMOVAL .
      Fig 3: Identifying Map Light Assembly Connector Terminal Identification
      GTY293846Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      15 (SNS2) - 12 (MCO-) Always Below 1 Ω

    NG → See step   9 

    OK: Go to next step 

  8. CHECK MAP LIGHT ASSEMBLY 
    1. Turn the ignition switch to ACC.
      Fig 4: Identifying Map Light Assembly Connector Terminal Identification
      GTY293624Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Connect an oscilloscope to terminals MCO+ and MCO- of the U2 map light assembly connector.
    3. Check the waveform of the telephone microphone assembly using an oscilloscope.
      RESULT

      Result Proceed to
      Waveform synchronized with voice input to telephone microphone assembly is output A
      Waveform synchronized with voice input to telephone microphone assembly is not output B
      TEXT IN ILLUSTRATION

      *a Component with harness connected
      (Map Light Assembly)

    B → See step   9 

    A → See step   18 

  9. REPLACE TELEPHONE MICROPHONE WITH ANOTHER AND CHECK 
    1. Replace the telephone microphone assembly with a new or normally functioning one, refer to REMOVAL .
    2. Check if the same problem occurs again.

      OK

      Malfunction disappears.

    NG → See step   16 

    OK → END (TELEPHONE MICROPHONE IS FAULTY) 

  10. CHECK NAVIGATION RECEIVER ASSEMBLY 
    1. Measure the voltage according to the value(s) in the table below.
      Fig 5: Identifying Navigation Receiver Assembly Connector Terminal Identification
      GTY215472Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      G20-17 (MACC) - Body ground Ignition switch ACC 5 V
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      G20-18 (SGND) - Body ground Always Below 1 Ω
      G20-20 (MIN-) - Body ground Always Below 1 Ω
      TEXT IN ILLUSTRATION

      *a Component with harness connected
      (Navigation Receiver Assembly)

    NG → See step   15 

    OK: Go to next step 

  11. CHECK HARNESS AND CONNECTOR (NAVIGATION RECEIVER - MAP LIGHT) 
    1. Disconnect the G20 navigation receiver assembly connector.
    2. Disconnect the U2 map light assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      G20-17 (MACC) - U2-14 (MACC) Always Below 1 Ω
      G20-19 (MIN+) - U2-13 (MCO+) Always Below 1 Ω
      G20-20 (MIN-) - U2-12 (MCO-) Always Below 1 Ω
      G20-5 (SNS2) - U2-15 (SNS2) Always Below 1 Ω
      G20-19 (MIN+) - Body ground Always 10 kΩ or higher
      G20-20 (MIN-) - Body ground Always 10 kΩ or higher
      G20-18 (SGND) - Body ground Always 10 kΩ or higher
      G20-5 (SNS2) - Body ground Always 10 kΩ or higher
      G20-17 (MACC) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  12. INSPECT MAP LIGHT ASSEMBLY 
    1. Remove the map light assembly, refer to REMOVAL .
      Fig 6: Identifying Map Light Assembly Connector Terminal Identification
      GTY293846Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      15 (SNS2) - 12 (MCO-) Always Below 1 Ω

    NG → See step   14 

    OK: Go to next step 

  13. CHECK MAP LIGHT ASSEMBLY 
    1. Turn the ignition switch to ACC.
      Fig 7: Identifying Map Light Assembly Connector Terminal Identification
      GTY293624Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Connect an oscilloscope to terminals MCO+ and MCO- of the U2 map light assembly connector.
    3. Check the waveform of the telephone microphone assembly using an oscilloscope.
      RESULT

      Result Proceed to
      Waveform synchronized with voice input to telephone microphone assembly is output A
      Waveform synchronized with voice input to telephone microphone assembly is not output B
      TEXT IN ILLUSTRATION

      *a Component with harness connected
      (Map Light Assembly)

    NG → See step   14 

    OK → See step   18 

  14. REPLACE TELEPHONE MICROPHONE WITH ANOTHER AND CHECK 
    1. Replace the telephone microphone assembly with a new or normally functioning one, refer to REMOVAL .
    2. Check if the same problem occurs again.

      OK

      Malfunction disappears.

    NG → See step   16 

    OK → END (TELEPHONE MICROPHONE IS FAULTY) 

  15. REPLACE NAVIGATION RECEIVER ASSEMBLY. Refer to  REMOVAL 
  16. REPLACE MAP LIGHT ASSEMBLY. Refer to  REMOVAL 
  17. REPLACE TELEMATICS TRANSCEIVER. Refer to  REMOVAL 
  18. PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE 
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