AUDIO / VIDEO: AUDIO AND VISUAL SYSTEM: Microphone Circuit between Microphone and Radio Receiver; 2018 MY Camry [03/2017 - 06/2017]

Last Modified: 11-20-2023	6.11:8.1.0	Doc ID: RM1000000012SEV
Model Year Start: 2018	Model: Camry	Prod Date Range: [03/2017 - 06/2017]
Title: AUDIO / VIDEO: AUDIO AND VISUAL SYSTEM: Microphone Circuit between Microphone and Radio Receiver; 2018 MY Camry [03/2017 - 06/2017]

Microphone Circuit between Microphone and Radio Receiver

DESCRIPTION

w/o Manual (SOS) Switch:
The radio and display receiver assembly, roof console box sub-assembly and telephone microphone assembly are connected to each other using the microphone connection detection signal lines.

Using this circuit, the radio and display receiver assembly sends power to the roof console box sub-assembly and telephone microphone assembly, and the roof console box sub-assembly and telephone microphone assembly sends microphone signals to the radio and display receiver assembly.
w/ Manual (SOS) Switch:
The radio and display receiver assembly, roof console box sub-assembly and telephone microphone assembly are connected to each other using the microphone connection detection signal lines.

Using this circuit, the DCM (telematics transceiver) sends power to the roof console box sub-assembly and telephone microphone assembly, and the roof console box sub-assembly and telephone microphone assembly sends microphone signals to the radio and display receiver assembly via the DCM (telematics transceiver).

WIRING DIAGRAM

w/ Sliding Roof

w/o Sliding Roof

CAUTION / NOTICE / HINT

NOTICE:

Depending on the parts that are replaced during vehicle inspection or maintenance, performing initialization, registration or calibration may be needed. Refer to Precaution for Audio and Visual System.
Click here
When replacing the radio and display receiver assembly, always replace it with a new one. If a radio and display receiver assembly which was installed to another vehicle is used, the following may occur:
- A communication malfunction DTC may be stored.
- The radio and display receiver assembly may not operate normally.
Before replacing the DCM (telematics transceiver), refer to Registration.
Click here

PROCEDURE

1.	CHECK MICROPHONE (OPERATION CHECK)

(a) Enter the "Microphone Check" screen. Refer to Check Microphone in Operation Check.

Click here

(b) When a voice is input into the microphone, check that the microphone input level meter changes according to the input voice.

OK:

Check result is normal.

Result	Proceed to
NG (w/ Sliding Roof and w/o Manual (SOS) Switch)	A
NG (w/ Sliding Roof and w/ Manual (SOS) Switch)	B
NG (w/o Sliding Roof)	C
OK	D

B

C

D

REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY

A

2.	CHECK HARNESS AND CONNECTOR (RADIO AND DISPLAY RECEIVER ASSEMBLY - ROOF CONSOLE BOX SUB-ASSEMBLY)

(a) Disconnect the K2 radio and display receiver assembly connector.

(b) Disconnect the V14 roof console box sub-assembly connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
K2-25 (SNS2) - V14-6 (SNS2)	Always	Below 1 Ω
K2-23 (MACC) - V14-9 (MACC)	Always	Below 1 Ω
K2-21 (MIN+) - V14-8 (MCO+)	Always	Below 1 Ω
K2-22 (MIN-) - V14-7 (MCO-)	Always	Below 1 Ω
K2-25 (SNS2) or V14-6 (SNS2) - Body ground	Always	10 kΩ or higher
K2-23 (MACC) or V14-9 (MACC) - Body ground	Always	10 kΩ or higher
K2-21 (MIN+) or V14-8 (MCO+) - Body ground	Always	10 kΩ or higher
K2-22 (MIN-) or V14-7 (MCO-) - Body ground	Always	10 kΩ or higher
K2-24 (SGND) - Body ground	Always	10 kΩ or higher

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

3.	INSPECT RADIO AND DISPLAY RECEIVER ASSEMBLY

(a) Connect the K2 radio and display receiver assembly connector.

(b) Connect the V14 roof console box sub-assembly connector.

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
K2-23 (MACC) - Body ground	Ignition switch ACC	4 to 6 V

*a	Component with harness connected (Radio and Display Receiver Assembly)

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
K2-24 (SGND) - Body ground	Always	Below 1 Ω
K2-22 (MIN-) - Body ground	Always	Below 1 Ω

NG

REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY

OK

4.	INSPECT ROOF CONSOLE BOX SUB-ASSEMBLY

(a) Remove the roof console box sub-assembly.

Click here

(b) Connect the MI2 telephone microphone assembly connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
6 (SNS2) - 7 (MCO-)	Always	Below 1 Ω

*a	Component without harness connected (Roof Console Box Sub-assembly)

NG

OK

5.	INSPECT ROOF CONSOLE BOX SUB-ASSEMBLY (OUTPUT TO RADIO AND DISPLAY RECEIVER ASSEMBLY)

(a) Connect the K2 radio and display receiver assembly connector.

(b) Connect the V14 roof console box sub-assembly connector.

(c) Turn the ignition switch to ACC.

(d) Connect an oscilloscope to terminals 8 (MCO+) and 7 (MCO-) of the V14 roof console box sub-assembly connector.

*a	Component with harness connected (Roof Console Box Sub-assembly)

(e) Check the signal waveform according to the condition(s) in the table below.

Item	Condition
Measurement terminal	V14-8 (MCO+) - V14-7 (MCO-)
Tool setting	50 mV/DIV., 500 ms/DIV.
Vehicle condition	Turn the ignition switch to ACC. Sound is input to the roof console box sub-assembly when the user is closer than 125 mm from the roof console box sub-assembly sound holes.

OK:

The waveform is similar to that shown in the illustration.

HINT:

The oscilloscope waveform shown in the illustration is an example for reference only.

OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

NG

6.	INSPECT ROOF CONSOLE BOX SUB-ASSEMBLY

(a) Remove the roof console box sub-assembly.

Click here

(b) Disconnect the MI2 telephone microphone assembly connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
V14-8 (MCO+) - MI2-3	Always	Below 1 Ω
V14-7 (MCO-) - MI2-2	Always	Below 1 Ω
V14-8 (MCO+) or MI2-3 - V14-15 (GND)	Always	Below 1 Ω
V14-7 (MCO-) or MI2-2 - V14-15 (GND)	Always	10 kΩ or higher

*a

Component without harness connected

(Roof Console Box Sub-assembly (No. 1 Roof Wire Side))

*b

Component without harness connected

(Roof Console Box Sub-assembly (Telephone Microphone Assembly Side))

OK

REPLACE TELEPHONE MICROPHONE ASSEMBLY

NG

REPLACE ROOF CONSOLE BOX SUB-ASSEMBLY

7.	INSPECT ROOF CONSOLE BOX SUB-ASSEMBLY

(a) Remove the roof console box sub-assembly.

Click here

(b) Disconnect the MI2 telephone microphone assembly connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
V14-6 (SNS2) - MI2-1	Always	Below 1 Ω
V14-7 (MCO-) - MI2-2	Always	Below 1 Ω
V14-6 (SNS2) or MI2-1 - V14-15 (GND)	Always	10 kΩ or higher
V14-7 (MCO-) or MI2-2 - V14-15 (GND)	Always	10 kΩ or higher

*a

Component without harness connected

(Roof Console Box Sub-assembly (No. 1 Roof Wire Side))

*b

Component without harness connected

(Roof Console Box Sub-assembly (Telephone Microphone Assembly Side))

OK

REPLACE TELEPHONE MICROPHONE ASSEMBLY

NG

REPLACE ROOF CONSOLE BOX SUB-ASSEMBLY

8.	CHECK HARNESS AND CONNECTOR (RADIO AND DISPLAY RECEIVER ASSEMBLY - ROOF CONSOLE BOX SUB-ASSEMBLY)

(a) Disconnect the K2 radio and display receiver assembly connector.

(b) Disconnect the V14 roof console box sub-assembly connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
K2-25 (SNS2) - V14-6 (SNS2)	Always	Below 1 Ω
K2-25 (SNS2) or V14-6 (SNS2) - Body ground	Always	10 kΩ or higher

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

9.	CHECK HARNESS AND CONNECTOR (RADIO AND DISPLAY RECEIVER ASSEMBLY - DCM (TELEMATICS TRANSCEIVER))

(a) Disconnect the K2 radio and display receiver assembly connector.

(b) Disconnect the K12 DCM (telematics transceiver) connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
K2-21 (MIN+) - K12-18 (MCO+)	Always	Below 1 Ω
K2-22 (MIN-) - K12-19 (MCO-)	Always	Below 1 Ω
K2-21 (MIN+) or K12-18 (MCO+) - Body ground	Always	10 kΩ or higher
K2-22 (MIN-) or K12-19 (MCO-) - Body ground	Always	10 kΩ or higher
K2-24 (SGND) - Body ground	Always	10 kΩ or higher

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

10.	CHECK HARNESS AND CONNECTOR (DCM (TELEMATICS TRANSCEIVER) - ROOF CONSOLE BOX SUB-ASSEMBLY)

(a) Disconnect the K12 DCM (telematics transceiver) connector.

(b) Disconnect the V14 roof console box sub-assembly connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
K12-33 (MCVD) - V14-9 (MACC)	Always	Below 1 Ω
K12-34 (MCI+) - V14-8 (MCO+)	Always	Below 1 Ω
K12-35 (MCI-) - V14-7 (MCO-)	Always	Below 1 Ω
K12-33 (MCVD) or V14-9 (MACC) - Body ground	Always	10 kΩ or higher
K12-34 (MCI+) or V14-8 (MCO+) - Body ground	Always	10 kΩ or higher
K12-35 (MCI-) or V14-7 (MCO-) - Body ground	Always	10 kΩ or higher
K12-32 (SGND) - Body ground	Always	10 kΩ or higher

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

11.	INSPECT RADIO AND DISPLAY RECEIVER ASSEMBLY

(a) Disconnect the K12 DCM (telematics transceiver) connector.

(b) Connect the K2 radio and display receiver assembly connector.

*a	Component with harness connected (Radio and Display Receiver Assembly)

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
K2-24 (SGND) - Body ground	Always	Below 1 Ω
K2-22 (MIN-) - Body ground	Always	Below 1 Ω

NG

REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY

OK

12.	INSPECT DCM (TELEMATICS TRANSCEIVER)

(a) Connect the K12 DCM (telematics transceiver) connector.

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
K12-33 (MCVD) - Body ground	Ignition switch ACC	4 to 6 V

*a	Component with harness connected (DCM (Telematics Transceiver))

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
K12-35 (MCI-) - Body ground	Always	Below 1 Ω
K12-32 (SGND) - Body ground	Always	Below 1 Ω

NG

REPLACE DCM (TELEMATICS TRANSCEIVER)

OK

13.	INSPECT ROOF CONSOLE BOX SUB-ASSEMBLY

(a) Remove the roof console box sub-assembly.

Click here

(b) Connect the MI2 telephone microphone assembly connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
6 (SNS2) - 7 (MCO-)	Always	Below 1 Ω

*a	Component without harness connected (Roof Console Box Sub-assembly)

NG

OK

14.	INSPECT ROOF CONSOLE BOX SUB-ASSEMBLY (OUTPUT TO DCM (TELEMATICS TRANSCEIVER))

(a) Connect the K2 radio and display receiver assembly connector.

(b) Connect the V14 roof console box sub-assembly connector.

(c) Connect the K12 DCM (telematics transceiver) connector.

(d) Turn the ignition switch to ACC.

(e) Connect an oscilloscope to terminals 8 (MCO+) and 7 (MCO-) of the V14 roof console box sub-assembly connector.

*a	Component with harness connected (Roof Console Box Sub-assembly)

(f) Check the signal waveform according to the condition(s) in the table below.

Item	Condition
Measurement terminal	V14-8 (MCO+) - V14-7 (MCO-)
Tool setting	50 mV/DIV., 500 ms/DIV.
Vehicle condition	Turn the ignition switch to ACC. Sound is input to the roof console box sub-assembly when the user is closer than 125 mm from the roof console box sub-assembly sound holes.

OK:

The waveform is similar to that shown in the illustration.

HINT:

The oscilloscope waveform shown in the illustration is an example for reference only.

NG

OK

15.	INSPECT DCM (TELEMATICS TRANSCEIVER) (OUTPUT TO RADIO AND DISPLAY RECEIVER ASSEMBLY)

(a) Connect the K2 radio and display receiver assembly connector.

(b) Connect the V14 roof console box sub-assembly connector.

(c) Connect the K12 DCM (telematics transceiver) connector.

(d) Turn the ignition switch to ACC.

(e) Connect an oscilloscope to terminals 18 (MCO+) and 19 (MCO-) of the K12 DCM (telematics transceiver) connector.

*a	Component with harness connected DCM (Telematics transceiver)

(f) Check the signal waveform according to the condition(s) in the table below.

Item	Condition
Measurement terminal	K12-18 (MCO+) - K12-19 (MCO-)
Tool setting	50 mV/DIV., 500 ms/DIV.
Vehicle condition	Turn the ignition switch to ACC. Sound is input to the roof console box sub-assembly when the user is closer than 125 mm from the roof console box sub-assembly sound holes.

OK:

The waveform is similar to that shown in the illustration.

HINT:

The oscilloscope waveform shown in the illustration is an example for reference only.

OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

NG

REPLACE DCM (TELEMATICS TRANSCEIVER)

16.	INSPECT ROOF CONSOLE BOX SUB-ASSEMBLY

(a) Remove the roof console box sub-assembly.

Click here

(b) Disconnect the MI2 telephone microphone assembly connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
V14-8 (MCO+) - MI2-3	Always	Below 1 Ω
V14-7 (MCO-) - MI2-2	Always	Below 1 Ω
V14-8 (MCO+) or MI2-3 - V14-15 (GND)	Always	Below 1 Ω
V14-7 (MCO-) or MI2-2 - V14-15 (GND)	Always	10 kΩ or higher

*a

Component without harness connected

(Roof Console Box Sub-assembly (No. 1 Roof Wire Side))

*b

Component without harness connected

(Roof Console Box Sub-assembly (Telephone Microphone Assembly Side))

OK

REPLACE TELEPHONE MICROPHONE ASSEMBLY

NG

REPLACE ROOF CONSOLE BOX SUB-ASSEMBLY

17.	INSPECT ROOF CONSOLE BOX SUB-ASSEMBLY

(a) Remove the roof console box sub-assembly.

Click here

(b) Disconnect the MI2 telephone microphone assembly connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
V14-6 (SNS2) - MI2-1	Always	Below 1 Ω
V14-7 (MCO-) - MI2-2	Always	Below 1 Ω
V14-6 (SNS2) or MI2-1 - V14-15 (GND)	Always	10 kΩ or higher
V14-7 (MCO-) or MI2-2 - V14-15 (GND)	Always	10 kΩ or higher

*a

Component without harness connected

(Roof Console Box Sub-assembly (No. 1 Roof Wire Side))

*b

Component without harness connected

(Roof Console Box Sub-assembly (Telephone Microphone Assembly Side))

OK

REPLACE TELEPHONE MICROPHONE ASSEMBLY

NG

REPLACE ROOF CONSOLE BOX SUB-ASSEMBLY

18.	CHECK HARNESS AND CONNECTOR (RADIO AND DISPLAY RECEIVER ASSEMBLY - ROOF CONSOLE BOX SUB-ASSEMBLY)

(a) Disconnect the K2 radio and display receiver assembly connector.

(b) Disconnect the V12 roof console box sub-assembly connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
K2-25 (SNS2) - V12-12 (SNS2)	Always	Below 1 Ω
K2-23 (MACC) - V12-9 (MACC)	Always	Below 1 Ω
K2-21 (MIN+) - V12-10 (MCO+)	Always	Below 1 Ω
K2-22 (MIN-) - V12-11 (MCO-)	Always	Below 1 Ω
K2-25 (SNS2) or V12-12 (SNS2) - Body ground	Always	10 kΩ or higher
K2-23 (MACC) or V12-9 (MACC) - Body ground	Always	10 kΩ or higher
K2-21 (MIN+) or V12-10 (MCO+) - Body ground	Always	10 kΩ or higher
K2-22 (MIN-) or V12-11 (MCO-) - Body ground	Always	10 kΩ or higher
K2-24 (SGND) - Body ground	Always	10 kΩ or higher

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

19.	INSPECT RADIO AND DISPLAY RECEIVER ASSEMBLY

(a) Connect the K2 radio and display receiver assembly connector.

(b) Connect the V12 roof console box sub-assembly connector.

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
K2-23 (MACC) - Body ground	Ignition switch ACC	4 to 6 V

*a	Component with harness connected (Radio and Display Receiver Assembly)

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
K2-24 (SGND) - Body ground	Always	Below 1 Ω
K2-22 (MIN-) - Body ground	Always	Below 1 Ω

NG

REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY

OK

20.	INSPECT ROOF CONSOLE BOX SUB-ASSEMBLY

(a) Remove the roof console box sub-assembly.

Click here

(b) Connect the MI2 telephone microphone assembly connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
12 (SNS2) - 11 (MCO-)	Always	Below 1 Ω

*a	Component without harness connected (Roof Console Box Sub-assembly)

NG

OK

21.	INSPECT ROOF CONSOLE BOX SUB-ASSEMBLY (OUTPUT TO RADIO AND DISPLAY RECEIVER ASSEMBLY)

(a) Connect the K2 radio and display receiver assembly connector.

(b) Connect the V12 roof console box sub-assembly connector.

(c) Turn the ignition switch to ACC.

(d) Connect an oscilloscope to terminals 10 (MCO+) and 11 (MCO-) of the V12 roof console box sub-assembly connector.

*a	Component with harness connected (Roof Console Box Sub-assembly)

(e) Check the signal waveform according to the condition(s) in the table below.

Item	Condition
Measurement terminal	V12-10 (MCO+) - V12-11 (MCO-)
Tool setting	50 mV/DIV., 500 ms/DIV.
Vehicle condition	Turn the ignition switch to ACC. Sound is input to the roof console box sub-assembly when the user is closer than 125 mm from the roof console box sub-assembly sound holes.

OK:

The waveform is similar to that shown in the illustration.

HINT:

The oscilloscope waveform shown in the illustration is an example for reference only.

OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

NG

22.	INSPECT ROOF CONSOLE BOX SUB-ASSEMBLY

(a) Remove the roof console box sub-assembly.

Click here

(b) Disconnect the MI2 telephone microphone assembly connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
V12-10 (MCO+) - MI2-3	Always	Below 1 Ω
V12-11 (MCO-) - MI2-2	Always	Below 1 Ω
V12-10 (MCO+) or MI2-3 - V12-4 (GND)	Always	Below 1 Ω
V12-11 (MCO-) or MI2-2 - V12-4 (GND)	Always	10 kΩ or higher

*a

Component without harness connected

(Roof Console Box Sub-assembly (No. 1 Roof Wire Side))

*b

Component without harness connected

(Roof Console Box Sub-assembly (Telephone Microphone Assembly Side))

OK

REPLACE TELEPHONE MICROPHONE ASSEMBLY

NG

REPLACE ROOF CONSOLE BOX SUB-ASSEMBLY

23.	INSPECT ROOF CONSOLE BOX SUB-ASSEMBLY

(a) Remove the roof console box sub-assembly.

Click here

(b) Disconnect the MI2 telephone microphone assembly connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
V12-12 (SNS2) - MI2-1	Always	Below 1 Ω
V12-11 (MCO-) - MI2-2	Always	Below 1 Ω
V12-12 (SNS2) or MI2-1 - V12-4 (GND)	Always	10 kΩ or higher
V12-11 (MCO-) or MI2-2 - V12-4 (GND)	Always	10 kΩ or higher

*a

Component without harness connected

(Roof Console Box Sub-assembly (No. 1 Roof Wire Side))

*b

Component without harness connected

(Roof Console Box Sub-assembly (Telephone Microphone Assembly Side))

OK

REPLACE TELEPHONE MICROPHONE ASSEMBLY

NG

REPLACE ROOF CONSOLE BOX SUB-ASSEMBLY