DTC B1579: Voice Recognition Microphone Disconnected [12/2019 - 10/2022]: Procedure

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

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   H2-22 (MIN-) - Body ground	Always	Below 1 Ω

   Result

   Result	Proceed to
   OK (w/ Telematics Transceiver)	A
   OK (w/o Telematics Transceiver)	B
   NG	C

Result: 

B 

See step  6

Result: 

C 

REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY. Refer to  REMOVAL [12/2019 - 10/2022] 

Result: 

A 

See step  2

1. Disconnect the H11 DCM (telematics transceiver) connector.
2. Disconnect the R12 telephone microphone assembly connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   H11-7 (MCI-) - R12-4 (MCO-)	Always	Below 1 Ω
   H11-7 (MCI-) or R12-4 (MCO-) - Body ground	Always	10 kΩ or higher

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  3

1. Disconnect the H2 radio and display receiver assembly connector.
2. Disconnect the H11 DCM (telematics transceiver) connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   H2-22 (MIN-) - H11-32 (MCO-)	Always	Below 1 Ω
   H2-22 (MIN-) or H11-32 (MCO-) - Body ground	Always	10 kΩ or higher

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  4

1. Disconnect the H2 radio and display receiver assembly connector.
2. Disconnect the R12 telephone microphone assembly connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   H2-25 (SNS2) - R12-3 (SNS2)	Always	Below 1 Ω
   H2-25 (SNS2) or R12-3 (SNS2) - Body ground	Always	10 kΩ or higher

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  5

1. Connect the H11 DCM (telematics transceiver) connector.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

2. Connect the H2 radio and display receiver assembly connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   H11-7 (MCI-) - Body ground	Always	Below 1 Ω

   Result

   Proceed to
   OK
   NG

Result: 

OK 

See step  7

Result: 

NG 

REPLACE DCM (TELEMATICS TRANSCEIVER). Refer to  REMOVAL [12/2019 - 10/2022] 

1. Disconnect the H2 radio and display receiver assembly connector.
2. Disconnect the R12 telephone microphone assembly connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   H2-25 (SNS2) - R12-3 (SNS2)	Always	Below 1 Ω
   H2-22 (MIN-) - R12-4 (MCO-)	Always	Below 1 Ω
   H2-25 (SNS2) or R12-3 (SNS2) - Body ground	Always	10 kΩ or higher
   H2-22 (MIN-) or R12-4 (MCO-) - Body ground	Always	10 kΩ or higher

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  7

1. Remove the telephone microphone assembly.

   Refer to REMOVAL [12/2019 - 10/2022]

2. 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

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Component without harness connected (Telephone Microphone Assembly)

   Result

   Proceed to
   OK
   NG

Result: 

OK 

REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY. Refer to  REMOVAL [12/2019 - 10/2022] 

Result: 

NG 

REPLACE TELEPHONE MICROPHONE ASSEMBLY. Refer to  REMOVAL [12/2019 - 10/2022]