NAVIGATION SYSTEM Microphone Circuit between Microphone and Radio Receiver

DESCRIPTION

• The multi-media module 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 multi-media module 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 multi-media module receiver assembly.

INSPECTION PROCEDURE

PROCEDURE

1. Click here

   CHECK HARNESS AND CONNECTOR (MULTI-MEDIA MODULE RECEIVER ASSEMBLY - MAP LIGHT ASSEMBLY)

   
   

   1. Disconnect the F77 multi-media module receiver assembly connector.

   2. Disconnect the R7 map light assembly connector.

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

      Standard Resistance

      Tester Connection Condition Specified Condition F77-49 (SNS2) - R7-20 (SNS2) Always Below 1 Ω F77-29 (MACC) - R7-25 (ACC) Always Below 1 Ω F77-27 (MIN+) - R7-27 (MI1+) Always Below 1 Ω F77-48 (MIN-) - R7-26 (MIC-) Always Below 1 Ω F77-49 (SNS2) - Body ground Always 10 kΩ or higher F77-29 (MACC) - Body ground Always 10 kΩ or higher F77-27 (MIN+) - Body ground Always 10 kΩ or higher F77-48 (MIN-) - Body ground Always 10 kΩ or higher F77-28 (SGND) - Body ground Always 10 kΩ or higher

   
   
   • OKClick here
   • NGClick here
2. Click here

   INSPECT MULTI-MEDIA MODULE RECEIVER ASSEMBLY

   
   
   1. 

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

      Standard Resistance
      Tester Connection Condition Specified Condition F77-28 (SGND) - Body ground Always Below 1 Ω F77-48 (MIN-) - Body ground Always Below 1 Ω

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition F77-29 (MACC) - Body ground Engine switch on (ACC) 4 to 6 V

      Table 1. Text in Illustration

      *a	Component with harness connected (Multi-media Module Receiver Assembly)

   
   
   • OKClick here
   • NGClick here
3. Click here

   INSPECT MAP LIGHT ASSEMBLY

   
   
   1. 

      Remove the map light assembly (Click here).

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

      Standard Resistance
      Tester Connection Condition Specified Condition 26 (MIC-) - 20 (SNS2) Always Below 1 Ω

   
   
   • OKClick here
   • NGClick here
4. Click here

   CHECK MAP LIGHT ASSEMBLY

   
   
   1. 

      Turn the engine switch on (ACC).

   2. Connect an oscilloscope to terminals R7-27 (MI1+) and R7-26 (MIC-) of the map light assembly connector.

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

      Table 2. Text in Illustration

      *a	Component with harness connected (Map Light Assembly)

      Table 3. 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

   
   
   • AClick here
   • BClick here
5. Click here

   CHECK TELEPHONE MICROPHONE ASSEMBLY

   
   

   1. Replace the telephone microphone assembly with a new or normally functioning one (Click here).

   2. Check if the same malfunction recurs.

      Table 4. Result

      Result	Proceed to
      Malfunction does not recur (returns to normal).	A
      Malfunction recurs.	B

   
   
   • AClick here
   • BClick here
6. Click here

   REPAIR OR REPLACE HARNESS OR CONNECTOR

7. Click here

   MULTI-MEDIA MODULE RECEIVER ASSEMBLYClick here

8. Click here

   PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLEClick here

9. Click here

   REPLACE MAP LIGHT ASSEMBLYClick here

10. Click here

    END (TELEPHONE MICROPHONE ASSEMBLY IS DEFECTIVE)