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AUDIO AND VISUAL SYSTEM > Microphone Circuit between Microphone and Radio Receiver

for Preparation Click here


DESCRIPTION

This circuit sends the microphone signal from the map light assembly (telephone microphone assembly) to the radio receiver assembly.
It also supplies power source from the radio receiver assembly to the map light assembly (telephone microphone assembly).

WIRING DIAGRAM


E190307E01


INSPECTION PROCEDURE

1.INSPECT RADIO RECEIVER ASSEMBLY


    E163028E11

  1. Disconnect the radio receiver assembly connector.

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

    Standard Voltage:
    Tester Connection
    		Condition
    		Specified Condition
    L45-3 (MACC) - Body ground
    		Power switch on (IG)
    		4 to 6 V

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    L45-6 (SGND) - Body ground
    		Always
    		Below 1 Ω
    L45-5 (MIN-) - Body ground
    		Always
    		Below 1 Ω

    Text in Illustration 
    *1
    		Component without harness connected
    (Radio Receiver Assembly)



NG
REPLACE RADIO RECEIVER ASSEMBLY (Click here)
OK


2.CONFIRM MODEL

  1. Choose the model to be inspected.

    Result:
    Model
    		Proceed to
    w/o Sliding Roof
    		A
    w/ Sliding Roof
    		B



B
Go to step 6
A


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


    E163029E13

  1. Disconnect the radio receiver assembly connector.



    E187118E02

  1. Disconnect the map light assembly connector.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    L45-1 (SNS2) - U3-2 (SNS2)
    		Always
    		Below 1 Ω
    L45-3 (MACC) - U3-5 (MACC)
    		Always
    		Below 1 Ω
    L45-2 (MIN+) - U3-4 (MCO+)
    		Always
    		Below 1 Ω
    L45-5 (MIN-) - U3-3 (MCO-)
    		Always
    		Below 1 Ω
    L45-1 (SNS2) - Body ground
    		Always
    		10 kΩ or higher
    L45-3 (MACC) - Body ground
    		Always
    		10 kΩ or higher
    L45-2 (MIN+) - Body ground
    		Always
    		10 kΩ or higher
    L45-5 (MIN-) - Body ground
    		Always
    		10 kΩ or higher
    L45-6 (SGND) - Body ground
    		Always
    		10 kΩ or higher

    Text in Illustration 
    *1
    		Front view of wire harness connector
    (to Radio Receiver Assembly)
    *2
    		Front view of wire harness connector
    (to Map Light Assembly)



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


4.INSPECT MAP LIGHT ASSEMBLY


    E187117E02

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    U3-2 (SNS2) - U3-3 (MCO-)
    		Always
    		Below 1 Ω

Text in Illustration 
*1
Component without harness connected
(Map Light Assembly)


NG
Go to step 9
OK


5.INSPECT MAP LIGHT ASSEMBLY

  1. Reconnect the radio receiver assembly connector.



    E187122E02

  1. Reconnect the map light assembly connector.

  1. Turn the power switch on (ACC).

  1. Connect an oscilloscope to terminals U3-4 (MCO+) and U3-3 (MCO-) of the map light assembly connector.

  1. Check the waveform of the telephone microphone assembly using an oscilloscope.

    Result:
    Result
    		Proceed to
    A waveform synchronized with the voice input to the telephone microphone assembly is output
    		A
    A waveform synchronized with the voice input to the telephone microphone assembly is not output
    		B

Text in Illustration 
*1
Component with harness connected
(Map Light Assembly)


B
Go to step 9
A

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

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


    E163029E13

  1. Disconnect the radio receiver assembly connector.



    E187215E02

  1. Disconnect the map light assembly connector.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    L45-1 (SNS2) - U13-3 (SNS2)
    		Always
    		Below 1 Ω
    L45-3 (MACC) - U13-6 (MACC)
    		Always
    		Below 1 Ω
    L45-2 (MIN+) - U13-5 (MCO+)
    		Always
    		Below 1 Ω
    L45-5 (MIN-) - U13-4 (MCO-)
    		Always
    		Below 1 Ω
    L45-1 (SNS2) - Body ground
    		Always
    		10 kΩ or higher
    L45-3 (MACC) - Body ground
    		Always
    		10 kΩ or higher
    L45-2 (MIN+) - Body ground
    		Always
    		10 kΩ or higher
    L45-5 (MIN-) - Body ground
    		Always
    		10 kΩ or higher
    L45-6 (SGND) - Body ground
    		Always
    		10 kΩ or higher

    Text in Illustration 
    *1
    		Front view of wire harness connector
    (to Radio Receiver Assembly)
    *2
    		Front view of wire harness connector
    (to Map Light Assembly)



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


7.INSPECT MAP LIGHT ASSEMBLY


    E187217E02

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    U13-3 (SNS2) - U13-4 (MCO-)
    		Always
    		Below 1 Ω

Text in Illustration 
*1
Component without harness connected
(Map Light Assembly)


NG
Go to step 9
OK


8.INSPECT MAP LIGHT ASSEMBLY

  1. Reconnect the radio receiver assembly connector.



    E187216E02

  1. Reconnect the map light assembly connector.

  1. Turn the power switch on (ACC).

  1. Connect an oscilloscope to terminals U13-5 (MCO+) and U13-4 (MCO-) of the map light assembly connector.

  1. Check the waveform of the telephone microphone assembly using an oscilloscope.

    Result:
    Result
    		Proceed to
    A waveform synchronized with the voice input to the telephone microphone assembly is output
    		A
    A waveform synchronized with the voice input to the telephone microphone assembly is not output
    		B

Text in Illustration 
*1
Component with harness connected
(Map Light Assembly)


B
Go to step 9
A

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

9.REPLACE TELEPHONE MICROPHONE ASSEMBLY

  1. Replace the telephone microphone assembly .

    HINT:
    1. w/o Sliding Roof (Click here)
    2. w/ Sliding Roof (Click here)

  1. Check if the same malfunction recurs.

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



B
REPLACE MAP LIGHT ASSEMBLY (Click here)
A

END