Microphone Circuit Between Overhead J/B and Multi-Display

AUDIO / VISUAL: AUDIO AND VISUAL SYSTEM: Microphone Circuit between Overhead J/B and Multi-display

Microphone Circuit between Overhead J/B and Multi-display

CAUTION / NOTICE / HINT
HINT: If the navigation type is NAVIGATION SYSTEM (for HDD), "multi-display" refers to the "display and navigation assembly".

DESCRIPTION

w/o LEXUS Link System:
This circuit sends a microphone signal from the microphone to the multi-display. It also supplies power from multi-display to the microphone.
w/ LEXUS Link System:
This circuit sends a microphone signal from the microphone to the multi-display through the mayday ECU. It also supplies power from the mayday ECU to the microphone.

WIRING DIAGRAM









INSPECTION PROCEDURE

PROCEDURE

1. CHECK DISPLAY AND NAVIGATION ASSEMBLY (MULTI-DISPLAY)




(a) Check the waveform of the microphone using an oscilloscope.






OK:
Waveform that matches sound spoken into microphone is output.






D -- CHECK LEXUS LINK SYSTEM
C -- REPLACE MULTI-DISPLAY
B -- REPLACE MULTI-DISPLAY
A -- REPLACE DISPLAY AND NAVIGATION ASSEMBLY
2. CHECK LEXUS LINK SYSTEM
(a) Check if the vehicle is equipped with the LEXUS link system.

Result





B -- CHECK HARNESS AND CONNECTOR (MAYDAY ECU - DISPLAY AND NAVIGATION ASSEMBLY AND OVERHEAD JUNCTION BLOCK)
A -- Continue to next step.
3. CHECK HARNESS AND CONNECTOR (OVERHEAD JUNCTION BLOCK - DISPLAY AND NAVIGATION ASSEMBLY [MULTI-DISPLAY])




(a) Disconnect the X4 junction block connector.
(b) Disconnect the L60 display connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard resistance:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
4. CHECK DISPLAY AND NAVIGATION ASSEMBLY [MULTI-DISPLAY] (MACC VOLTAGE)




(a) Reconnect the L60 display connector.
(b) Measure the voltage according to the value(s) in the table below.
Standard voltage:






Result





D -- REPLACE MULTI-DISPLAY
C -- REPLACE MULTI-DISPLAY
B -- REPLACE DISPLAY AND NAVIGATION ASSEMBLY
A -- Continue to next step.
5. CHECK MICROPHONE ASSEMBLY




(a) Remove the microphone from the overhead junction block Removal.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:






NG -- REPLACE MICROPHONE ASSEMBLY
OK -- PROCEED TO NEXT INSPECTION PROCEDURE SHOWN IN PROBLEM SYMPTOMS TABLE
6. CHECK HARNESS AND CONNECTOR (MAYDAY ECU - DISPLAY AND NAVIGATION ASSEMBLY AND OVERHEAD JUNCTION BLOCK)




(a) Disconnect the R24 ECU connector.
(b) Disconnect the L60 display connector.
(c) Disconnect the X4 block connector.
(d) Measure the resistance according to the value(s) in the table below.
Standard resistance:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
7. CHECK MAYDAY ECU (TACC VOLTAGE)




(a) Reconnect the R24 ECU connector.
(b) Measure the voltage according to the value(s) in the table below.
Standard voltage:






NG -- REPLACE MAYDAY ECU
OK -- Continue to next step.
8. CHECK MICROPHONE ASSEMBLY




(a) Remove the microphone from the overhead junction block Removal.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:






NG -- REPLACE MICROPHONE ASSEMBLY
OK -- PROCEED TO NEXT INSPECTION PROCEDURE SHOWN IN PROBLEM SYMPTOMS TABLE