Last Modified: 04-05-2023 6.11:8.1.0 Doc ID: RM100000001DP2E
Model Year Start: 2019 Model: Sienna Prod Date Range: [08/2018 -           ]
Title: AUDIO / VIDEO: AUDIO AND VISUAL SYSTEM: B1579; Voice Recognition Microphone Disconnected; 2019 - 2020 MY Sienna [08/2018 -        ]

DTC

B1579

Voice Recognition Microphone Disconnected

DESCRIPTION

The radio and display receiver assembly and microphone amplifier 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 Code

DTC Detection Condition

Trouble Area

B1579

Telephone microphone signal is lost.
  • Radio and display receiver assembly
  • Microphone Amplifier Assembly
  • Harness or connector
  • DCM (telematics transceiver) (w/ Manual [SOS] Switch)

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

  • 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 occurs:
    • 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 2018 - 2020 MY Sienna [11/2017 -        ]; CELLULAR COMMUNICATION: SAFETY CONNECT SYSTEM: DCM ACTIVATION

HINT:

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 2018 - 2020 MY Sienna [11/2017 -        ]; AUDIO / VIDEO: AUDIO AND VISUAL SYSTEM: PRECAUTION

PROCEDURE

1.

CHECK VEHICLE TYPE

(a) Check the vehicle type.

Result

Proceed to

w/ Manual (SOS) Switch

A

w/o Manual (SOS) Switch

B
B

GO TO STEP 7

A

2.

CHECK HARNESS AND CONNECTOR (RADIO AND DISPLAY RECEIVER ASSEMBLY - MICROPHONE AMPLIFIER ASSEMBLY)

(a) Disconnect the D196 radio and display receiver assembly connector.

(b) Disconnect the T34 microphone amplifier assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

D196-25 (SNS2) - T34-3 (SNS2)

Always

Below 1 Ω

D196-25 (SNS2) - Body ground

Always

10 kΩ or higher
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

3.

CHECK HARNESS AND CONNECTOR (DCM [TELEMATICS TRANSCEIVER] - MICROPHONE AMPLIFIER ASSEMBLY)

(a) Disconnect the D73 DCM (telematics transceiver) connector.

(b) Disconnect the T34 microphone amplifier assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

D73-35 (MCI-) - T34-4 (MIC-)

Always

Below 1 Ω

D73-35 (MCI-) - 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 D196 radio and display receiver assembly connector.

(b) Disconnect the D73 DCM (telematics transceiver) connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

D196-22 (MIN-) - D73-19 (MCO-)

Always

Below 1 Ω

D196-22 (MIN-) - Body ground

Always

10 kΩ or higher
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

5.

CHECK DCM (TELEMATICS TRANSCEIVER) (MCI-)

(a) Remove the DCM (telematics transceiver) with the connector(s) still connected.

*a

Component with harness connected

(DCM [Telematics Transceiver])

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

D73-35 (MCI-) - Body ground

Always

Below 1 Ω
NG

REPLACE DCM (TELEMATICS TRANSCEIVER)

OK

6.

INSPECT MICROPHONE AMPLIFIER ASSEMBLY (SNS2, MCO-)

(a) Remove the microphone amplifier assembly.

Click here 2019 - 2020 MY Sienna [08/2018 -        ]; AUDIO / VIDEO: MICROPHONE AMPLIFIER: REMOVAL

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

3 (SNS2) - 4 (MIC-)

Always

Below 1 Ω

*a

Component without harness connected

(Microphone Amplifier Assembly)
OK

REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY

NG

REPLACE MICROPHONE AMPLIFIER ASSEMBLY

7.

CHECK HARNESS AND CONNECTOR (RADIO AND DISPLAY RECEIVER ASSEMBLY - MICROPHONE AMPLIFIER ASSEMBLY)

(a) Disconnect the D196 radio and display receiver assembly connector.

(b) Disconnect the T34 microphone amplifier assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

D196-25 (SNS2) - T34-3 (SNS2)

Always

Below 1 Ω

D196-22 (MIN-) - T34-4 (MIC-)

Always

Below 1 Ω

D196-25 (SNS2) - Body ground

Always

10 kΩ or higher

D196-22 (MIN-) - Body ground

Always

10 kΩ or higher
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

8.

INSPECT MICROPHONE AMPLIFIER ASSEMBLY (SNS2, MCO-)

(a) Remove the microphone amplifier assembly.

Click here 2019 - 2020 MY Sienna [08/2018 -        ]; AUDIO / VIDEO: MICROPHONE AMPLIFIER: REMOVAL

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

3 (SNS2) - 4 (MIC-)

Always

Below 1 Ω

*a

Component without harness connected

(Microphone Amplifier Assembly)
OK

REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY

NG

REPLACE MICROPHONE AMPLIFIER ASSEMBLY