Last Modified: 08-21-2023 6.11:8.1.0 Doc ID: RM100000001SDXW
Model Year Start: 2021 Model: Avalon Prod Date Range: [08/2020 -           ]
Title: AUDIO / VIDEO: AUDIO AND VISUAL SYSTEM (for Gasoline Model): B1579; Voice Recognition Microphone Disconnected; 2021 - 2022 MY Avalon [08/2020 -        ]

DTC

B1579

Voice Recognition Microphone Disconnected

DESCRIPTION

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.

This DTC is stored when a microphone connection detection signal line is disconnected.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

B1579

Voice Recognition Microphone Disconnected

Microphone signal is lost
  • Roof console box sub-assembly
  • Telephone microphone assembly
  • Radio and display receiver assembly
  • DCM (telematics transceiver)
  • Harness or connector

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 2019 - 2021 MY Avalon [04/2018 - 08/2021]; AUDIO / VIDEO: AUDIO AND VISUAL SYSTEM (for Gasoline Model): PRECAUTION 2022 MY Avalon [08/2021 -        ]; AUDIO / VIDEO: AUDIO AND VISUAL SYSTEM (for Gasoline Model): PRECAUTION

  • 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 2021 - 2022 MY Avalon [08/2020 -        ]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, Gasoline Model): REGISTRATION

PROCEDURE

1.

CHECK MODEL

(a) Choose the model to be inspected.

Result

Proceed to

w/ Sliding Roof

A

w/o Sliding Roof

B
B

GO TO STEP 9

A

2.

INSPECT RADIO AND DISPLAY RECEIVER ASSEMBLY

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

G2-22 (MIN-) - Body ground

Always

Below 1 Ω

Result:

Proceed to

OK

NG

*a

Component with harness connected

(Radio and Display Receiver Assembly)
NG

REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY

OK

3.

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

(a) Disconnect the G124 DCM (telematics transceiver) connector.

(b) Disconnect the O10 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

G124-7 (MCI-) - O10-7 (MCO-)

Always

Below 1 Ω

G124-7 (MCI-) or O10-7 (MCO-) - Body ground

Always

10 kΩ or higher
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

4.

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

(a) Disconnect the G2 radio and display receiver assembly connector.

(b) Disconnect the G124 DCM (telematics transceiver) connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

G2-22 (MIN-) - G124-32 (MCO-)

Always

Below 1 Ω

G2-22 (MIN-) or G124-32 (MCO-) - Body ground

Always

10 kΩ or higher
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

5.

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

(a) Disconnect the G2 radio and display receiver assembly connector.

(b) Disconnect the O10 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

G2-25 (SNS2) - O10-6 (SNS2)

Always

Below 1 Ω

G2-25 (SNS2) or O10-6 (SNS2) - Body ground

Always

10 kΩ or higher
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

6.

INSPECT DCM (TELEMATICS TRANSCEIVER)

(a) Connect the G124 DCM (telematics transceiver) connector.

(b) Connect the G2 radio and display receiver assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

G124-7 (MCI-) - Body ground

Always

Below 1 Ω

*a

Component with harness connected

(DCM (Telematics Transceiver))
NG

REPLACE DCM (TELEMATICS TRANSCEIVER)

OK

7.

INSPECT ROOF CONSOLE BOX SUB-ASSEMBLY

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

Click here 2019 - 2022 MY Avalon Avalon HV [04/2018 -        ]; LIGHTING (INT): PERSONAL LIGHT: REMOVAL

(b) Connect the B 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)
OK

REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY

NG

8.

INSPECT ROOF CONSOLE BOX SUB-ASSEMBLY

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

Click here 2019 - 2022 MY Avalon Avalon HV [04/2018 -        ]; LIGHTING (INT): PERSONAL LIGHT: REMOVAL

(b) Disconnect the B telephone microphone assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

B-1 - O10-6 (SNS2)

Always

Below 1 Ω

B-2 - O10-7 (MCO-)

Always

Below 1 Ω

B-1 or O10-6 (SNS2) - O10-15 (GND)

Always

10 kΩ or higher

B-2 or O10-7 (MCO-) - O10-15 (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

9.

INSPECT RADIO AND DISPLAY RECEIVER ASSEMBLY

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

G2-22 (MIN-) - Body ground

Always

Below 1 Ω

Result:

Proceed to

OK

NG

*a

Component with harness connected

(Radio and Display Receiver Assembly)
NG

REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY

OK

10.

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

(a) Disconnect the G124 DCM (telematics transceiver) connector.

(b) Disconnect the O9 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

G124-7 (MCI-) - O9-4 (MCO-)

Always

Below 1 Ω

G124-7 (MCI-) or O9-4 (MCO-) - Body ground

Always

10 kΩ or higher
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

11.

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

(a) Disconnect the G2 radio and display receiver assembly connector.

(b) Disconnect the G124 DCM (telematics transceiver) connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

G2-22 (MIN-) - G124-32 (MCO-)

Always

Below 1 Ω

G2-22 (MIN-) or G124-32 (MCO-) - Body ground

Always

10 kΩ or higher
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

12.

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

(a) Disconnect the G2 radio and display receiver assembly connector.

(b) Disconnect the O9 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

G2-25 (SNS2) - O9-3 (SNS2)

Always

Below 1 Ω

G2-25 (SNS2) or O9-3 (SNS2) - Body ground

Always

10 kΩ or higher
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

13.

INSPECT DCM (TELEMATICS TRANSCEIVER)

(a) Connect the G124 DCM (telematics transceiver) connector.

(b) Connect the G2 radio and display receiver assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

G124-7 (MCI-) - Body ground

Always

Below 1 Ω

*a

Component with harness connected

(DCM (Telematics Transceiver))
NG

REPLACE DCM (TELEMATICS TRANSCEIVER)

OK

14.

INSPECT ROOF CONSOLE BOX SUB-ASSEMBLY

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

Click here 2019 - 2022 MY Avalon Avalon HV [04/2018 -        ]; LIGHTING (INT): PERSONAL LIGHT: REMOVAL

(b) Connect the B telephone microphone assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

3 (SNS2) - 4 (MCO-)

Always

Below 1 Ω

*a

Component without harness connected

(Roof Console Box Sub-assembly)
OK

REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY

NG

15.

INSPECT ROOF CONSOLE BOX SUB-ASSEMBLY

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

Click here 2019 - 2022 MY Avalon Avalon HV [04/2018 -        ]; LIGHTING (INT): PERSONAL LIGHT: REMOVAL

(b) Disconnect the B telephone microphone assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

B-1 - O9-3 (SNS2)

Always

Below 1 Ω

B-2 - O9-4 (MCO-)

Always

Below 1 Ω

B-1 or O9-3 (SNS2) - O9-11 (GND)

Always

10 kΩ or higher

B-2 or O9-4 (MCO-) - O9-11 (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