AUDIO AND VISUAL SYSTEM (w/o Navigation System) > Microphone Circuit between Microphone and Radio Receiver

for Preparation Click here


DESCRIPTION

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

WIRING DIAGRAM


E223339E01


INSPECTION PROCEDURE

1.CHECK HARNESS AND CONNECTOR

  1. Disconnect the radio receiver assembly and map light assembly connectors.

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

    Standard Resistance:
    for 10 Speakers 
    Tester Connection
    		Condition
    		Specified Condition
    H54-1 (SNS2) - T6-11 (SNS2)
    		Always
    		Below 1 Ω
    H54-3 (MACC) - T6-14 (MACC)
    		Always
    		Below 1 Ω
    H54-2 (MIN+) - T6-13 (MCO+)
    		Always
    		Below 1 Ω
    H54-5 (MIN-) - T6-12 (MCO-)
    		Always
    		Below 1 Ω
    H54-1 (SNS2) - Body ground
    		Always
    		10 kΩ or higher
    H54-3 (MACC) - Body ground
    		Always
    		10 kΩ or higher
    H54-2 (MIN+) - Body ground
    		Always
    		10 kΩ or higher
    H54-5 (MIN-) - Body ground
    		Always
    		10 kΩ or higher
    H54-6 (SGND) - Body ground
    		Always
    		10 kΩ or higher
    for 6 Speakers 
    Tester Connection
    		Condition
    		Specified Condition
    H47-6 (SNS2) - T6-11 (SNS2)
    		Always
    		Below 1 Ω
    H47-4 (MACC) - T6-14 (MACC)
    		Always
    		Below 1 Ω
    H47-5 (MIN+) - T6-13 (MCO+)
    		Always
    		Below 1 Ω
    H47-19 (MIN-) - T6-12 (MCO-)
    		Always
    		Below 1 Ω
    H47-6 (SNS2) - Body ground
    		Always
    		10 kΩ or higher
    H47-4 (MACC) - Body ground
    		Always
    		10 kΩ or higher
    H47-5 (MIN+) - Body ground
    		Always
    		10 kΩ or higher
    H47-19 (MIN-) - Body ground
    		Always
    		10 kΩ or higher
    H47-18 (SGND) - Body ground
    		Always
    		10 kΩ or higher



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


2.INSPECT RADIO RECEIVER ASSEMBLY

  1. Disconnect the radio receiver assembly connector.



    E222799E01

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

    Standard Voltage:
    for 10 Speakers 
    Tester Connection
    		Condition
    		Specified Condition
    H54-3 (MACC) - Body ground
    		Power switch on (ACC)
    		4 to 6 V
    for 6 Speakers 
    Tester Connection
    		Condition
    		Specified Condition
    H47-4 (MACC) - Body ground
    		Power switch on (ACC)
    		4 to 6 V

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

    Standard Resistance:
    for 10 Speakers 
    Tester Connection
    		Condition
    		Specified Condition
    H54-6 (SGND) - Body ground
    		Always
    		Below 1 Ω
    H54-5 (MIN-) - Body ground
    		Always
    		Below 1 Ω
    for 6 Speakers 
    Tester Connection
    		Condition
    		Specified Condition
    H47-18 (SGND) - Body ground
    		Always
    		Below 1 Ω
    H47-19 (MIN-) - Body ground
    		Always
    		Below 1 Ω

    Text in Illustration 
    *A
    		for 10 Speakers
    *B
    		for 6 Speakers
    *a
    		Component without harness connected
    (Radio Receiver Assembly)



NG
REPLACE RADIO RECEIVER ASSEMBLY (Click here)
OK


3.INSPECT MAP LIGHT ASSEMBLY


    E197890E11

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    T6-12 (MCO-) - T6-11 (SNS2)
    		Always
    		Below 1 Ω

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


NG
Go to step 5
OK


4.INSPECT MAP LIGHT ASSEMBLY

  1. Reconnect the radio receiver assembly connector.



    E198451E02

  1. Reconnect the map light assembly connector.

  1. Turn the power switch on (ACC).

  1. Connect an oscilloscope to terminals 13 (MCO+) and 12 (MCO-) of the map light assembly connector.

  1. 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

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


B
Go to step 5
A

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

5.REPLACE TELEPHONE MICROPHONE ASSEMBLY

  1. Replace the telephone microphone assembly (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