AUDIO AND VISUAL SYSTEM(for Radio and Display Type) Microphone Circuit between Microphone and Radio Receiver

DESCRIPTION

• The radio and display receiver assembly and map light assembly (telephone microphone assembly) are connected to each other using the microphone connection detection signal lines.

• Using this circuit, the radio and display receiver assembly sends power to the map light assembly (telephone microphone assembly), and the map light assembly (telephone microphone assembly) sends microphone signals to the radio and display receiver assembly.

WIRING DIAGRAM

PROCEDURE

1. CHECK MICROPHONE (OPERATION CHECK)

   
   

   1. 

      Enter the "Microphone Check" screen. Refer to Check Microphone in Operation Check.

      Click here

   2. When a voice is input into the microphone, check that the microphone input level meter changes according to the input voice.

   3. Push the recording switch and perform voice recording.

      Tech Tips

      
      

      • Select the recording switch with the blower motor of the air conditioning system stopped. If an outlet of the air conditioning system is facing the microphone, noise may be recorded.

      • Voice can be recorded for up to 5 seconds.

   4. Check that the recording indicator remains on while recording and that the recorded voice is played normally without noise or distortion.

      OK
      All check results are normal.

      Result
      Proceed to OK NG

   
   

   OK

   REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY Click here

   NG

2. CHECK HARNESS AND CONNECTOR (RADIO AND DISPLAY RECEIVER ASSEMBLY - MAP LIGHT ASSEMBLY)

   
   

   1. Disconnect the G37 radio and display receiver assembly connector.

   2. Disconnect the Q3 map light assembly (telephone microphone assembly) connector.

   3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition G37-4 (MACC) - Q3-15 (MACC) Always Below 1 Ω G37-5 (MIN+) - Q3-14 (MCO+) Always Below 1 Ω G37-19 (MIN-) - Q3-13 (MCO-) Always Below 1 Ω G37-18 (SGND) - Body ground Always 10 kΩ or higher G37-4 (MACC) or Q3-15 (MACC) - Body ground Always 10 kΩ or higher G37-5 (MIN+) or Q3-14 (MCO+) - Body ground Always 10 kΩ or higher G37-19 (MIN-) or Q3-13 (MCO-) - Body ground Always 10 kΩ or higher

      Result
      Proceed to OK NG

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR

   OK

3. INSPECT MAP LIGHT ASSEMBLY

   
   

   1. Remove the map light assembly.

      Click here

   2. Inspect the map light assembly.

      Click here

      Result
      Proceed to OK NG

   
   

   NG

   REPLACE MAP LIGHT ASSEMBLY Click here

   OK

4. CHECK RADIO AND DISPLAY RECEIVER ASSEMBLY

   
   
   1. 

      *a	Component with harness connected (Radio and Display Receiver Assembly)

      Remove the radio and display receiver assembly with the connector still connected.

   2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition G37-19 (MIN-) - Body ground Always Below 1 Ω

   3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Switch Condition Specified Condition G37-4 (MACC) - Body ground Ignition switch ACC 4 to 6 V

      Result
      Proceed to OK NG

   
   

   NG

   REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY Click here

   OK

5. CHECK MAP LIGHT ASSEMBLY

   
   
   1. 

      *a	Component with harness connected (Map Light Assembly)

      Reconnect the map light assembly with the connector still connected.

   2. Turn the ignition switch to ACC.

   3. Connect an oscilloscope to terminals Q3-14 (MCO+) and Q3-13 (MCO-) of the map light assembly connector.

   4. Check the waveform of the telephone microphone assembly using the oscilloscope.

      Result
      Result Proceed to A waveform synchronized with the voice input to the map light assembly is not output. A A waveform synchronized with the voice input to the map light assembly is output. B

   
   

   A

   REPLACE TELEPHONE MICROPHONE ASSEMBLY Click here

   B

   REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY Click here