NAVIGATION SYSTEM(for HDD) Microphone Circuit between Microphone and Navigation Receiver Assembly

DESCRIPTION

• The navigation ECU sub-assembly and map light assembly (telephone microphone assembly) are connected to each other using the microphone connection detection signal lines.

• Using this circuit, the navigation ECU sub-assembly sends power to the map light assembly (telephone microphone assembly), and the map light assembly (telephone microphone assembly) sends microphone signals to the navigation ECU sub-assembly.

WIRING DIAGRAM

*a	Telephone Microphone Assembly
*b	Shielded
*c	Map Light Assembly
*d	Navigation ECU Sub-assembly

PROCEDURE

1. CHECK HARNESS AND CONNECTOR (NAVIGATION ECU SUB-ASSEMBLY - MAP LIGHT ASSEMBLY [TELEPHONE MICROPHONE ASSEMBLY])

   
   

   1. Disconnect the G139 navigation ECU sub-assembly connector.

   2. Disconnect the Q7 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 G139-4 (MACC) - Q7-11 (MACC) Always Below 1 Ω G139-5 (MIN+) - Q7-10 (MCO+) Always Below 1 Ω G139-19 (MIN-) - Q7-9 (MCO-) Always Below 1 Ω G139-6 (SNS2) - Q7-12 (SNS2) Always Below 1 Ω G139-4 (MACC) - Body ground Always 10 kΩ or higher G139-5 (MIN+) - Body ground Always 10 kΩ or higher G139-19 (MIN-) - Body ground Always 10 kΩ or higher G139-18 (SGND) - Body ground Always 10 kΩ or higher G139-6 (SNS2) - Body ground Always 10 kΩ or higher

      Result
      Proceed to OK NG

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR

   OK

2. INSPECT NAVIGATION ECU SUB-ASSEMBLY

   
   
   1. 

      *a	Component with harness connected (Navigation ECU Sub-assembly)

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

      Standard Resistance
      Tester Connection Condition Specified Condition G139-18 (SGND) - Body ground Always Below 1 Ω G139-19 (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 G139-4 (MACC) - Body ground Ignition switch ACC 4 to 6 V

      Result
      Proceed to OK NG

   
   

   NG

   PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here

   OK

3. INSPECT MAP LIGHT ASSEMBLY (TELEPHONE MICROPHONE ASSEMBLY)

   
   

   1. 

      Remove the map light assembly (telephone microphone assembly).

      Click here

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

      Standard Resistance
      Tester Connection Condition Specified Condition 12 (SNS2) - 9 (MCO-) Always Below 1 Ω

      Result
      Proceed to OK NG

   
   

   NG

   CHECK TELEPHONE MICROPHONE ASSEMBLY Click here

   OK

4. CHECK MAP LIGHT ASSEMBLY

   
   
   1. 

      *a	Component with harness connected (Map Light Assembly)

      Remove the map light assembly with its connector still connectoed.

      Click here

   2. Turn the ignition switch to ACC.

   3. Connect an oscilloscope to terminals 10 (MCO+) and 9 (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 output A A waveform synchronized with the voice input to the map light assembly is not output B

   
   

   A

   PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here

   B

5. CHECK TELEPHONE MICROPHONE ASSEMBLY

   
   

   1. Replace the telephone microphone assembly with a new or normally functioning one.

      Click here

   2. Check if the same problem occurs again.

      Result
      Proceed to Malfunction disappears Malfunction does not disappear

   
   

   Malfunction disappears

   END (TELEPHONE MICROPHONE ASSEMBLY IS DEFECTIVE)

   Malfunction does not disappear

6. CHECK MAP LIGHT ASSEMBLY

   
   

   1. Replace the map light assembly with a new or normally functioning one.

      Click here

   2. Check if the same problem occurs again.

      Result
      Proceed to Malfunction disappears Malfunction does not disappear

   
   

   Malfunction disappears

   END (MAP LIGHT ASSEMBLY IS DEFECTIVE)

   Malfunction does not disappear

   PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here

7. CHECK TELEPHONE MICROPHONE ASSEMBLY

   
   

   1. Replace the telephone microphone assembly with a new or normally functioning one.

      Click here

   2. Check if the same problem occurs again.

      Result
      Proceed to Malfunction disappears Malfunction does not disappear

   
   

   Malfunction disappears

   END (TELEPHONE MICROPHONE ASSEMBLY IS DEFECTIVE)

   Malfunction does not disappear

   REPLACE MAP LIGHT ASSEMBLY Click here