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

DTC Code DTC Name
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

E270427E01

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. E176671C31

      *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

      Engine switch on (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. E244514E04

      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 ASSEMBLYClick here

    OK

  4. CHECK MAP LIGHT ASSEMBLY

    1. E244515C02

      *a

      Component with harness connected

      (Map Light Assembly)

      Remove the map light assembly with its connector still connectoed.

      Click here

    2. Turn the engine switch on (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