Microphone Circuit between Overhead J/B and Multi-display
AUDIO / VIDEO: AUDIO AND VISUAL SYSTEM: Microphone Circuit between Overhead J/B and Multi-display
Microphone Circuit between Overhead J/B and Multi-display
DESCRIPTION
w/o LEXUS Link System:
This circuit sends a microphone signal from the microphone to the multi-display. It also supplies power from the multi-display to the microphone.
w/ LEXUS Link System:
This circuit sends a microphone signal from the microphone to the display and module display through the telephone ECU assembly. It also supplies power from the telephone ECU assembly to the microphone.
WIRING DIAGRAM
INSPECTION PROCEDURE
PROCEDURE
1. CHECK DISPLAY AND NAVIGATION MODULE DISPLAY OR MULTI-DISPLAY
(a) Check the waveform of the microphone using an oscilloscope.
C -- CHECK LEXUS LINK SYSTEM
B -- REPLACE MULTI-DISPLAY ASSEMBLY
A -- REPLACE DISPLAY AND NAVIGATION MODULE DISPLAY
2. CHECK LEXUS LINK SYSTEM
(a) Check if the vehicle is equipped with the LEXUS link system.
Result
B -- CHECK HARNESS AND CONNECTOR (TELEPHONE ECU - MULTI-DISPLAY AND OVERHEAD JUNCTION BLOCK)
A -- Continue to next step.
3. CHECK HARNESS AND CONNECTOR (OVERHEAD JUNCTION BLOCK - MULTI-DISPLAY)
(a) Disconnect the R7 overhead junction block connector.
(b) Disconnect the F27 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 MULTI-DISPLAY (MACC VOLTAGE)
(a) Reconnect the F27 display connector.
(b) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
Result
C -- REPLACE MULTI-DISPLAY ASSEMBLY
B -- REPLACE DISPLAY AND NAVIGATION MODULE DISPLAY
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 CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
6. CHECK HARNESS AND CONNECTOR (TELEPHONE ECU - MULTI-DISPLAY AND OVERHEAD JUNCTION BLOCK)
(a) Disconnect the P2 ECU connector.
(b) Disconnect the F27 display connector.
(c) Disconnect the R7 junction 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 TELEPHONE ECU ASSEMBLY (TACC VOLTAGE)
(a) Reconnect the P2 ECU connector.
(b) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
NG -- REPLACE TELEPHONE ECU ASSEMBLY
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 CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE