Toyota CH-R Service Manual: Voice Recognition Microphone Disconnected (B1579)

Toyota CH-R Service Manual / Audio / Video / Audio And Visual System(for Radio And Display Type) / Voice Recognition Microphone Disconnected (B1579)

DESCRIPTION

The radio and display receiver assembly and map light assembly (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	Telephone microphone signal is lost.	Map light assembly (telephone microphone assembly) Radio and display receiver 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 or navigation ECU, always replace it with a new one. If a radio and display receiver assembly or navigation ECU which was installed to another vehicle is used, the following may occur:
- A communication malfunction DTC is stored.
- The radio and display receiver assembly or navigation ECU may not operate normally.
If the DCM (telematics transceiver) has been replaced, perform the DCM Activation procedure using the Techstream (w/ Manual (SOS) Switch).

PROCEDURE

1.	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
F131-22 (MIN-) - Body ground	Always	Below 1 Ω

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

REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY

2.	CONFIRM MODEL

(a) Choose the model to be inspected.

Result	Proceed to
w/ Manual (SOS) Switch	A
w/o Manual (SOS) Switch	B

GO TO STEP 7

3.	CHECK HARNESS AND CONNECTOR (DCM (TELEMATICS TRANSCEIVER) - MAP LIGHT ASSEMBLY (TELEPHONE MICROPHONE ASSEMBLY))

(a) Disconnect the F134 DCM (telematics transceiver) connector.

(b) Disconnect the R2 map light assembly (telephone microphone assembly) connector.

Standard Resistance:

Tester Connection	Condition	Specified Condition
F134-35 (MIC-) - R2-7 (MCO-)	Always	Below 1 Ω
F134-35 (MIC-) - Body ground	Always	10 kΩ or higher

REPAIR OR REPLACE HARNESS OR CONNECTOR

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

(a) Disconnect the F131 radio and display receiver assembly connector.

(b) Disconnect the F134 DCM (telematics transceiver) connector.

Standard Resistance:

Tester Connection	Condition	Specified Condition
F131-22 (MIN-) - F134-19 (MCO-)	Always	Below 1 Ω
F131-22 (MIN-) - Body ground	Always	10 kΩ or higher

REPAIR OR REPLACE HARNESS OR CONNECTOR

5.	CHECK HARNESS AND CONNECTOR (RADIO AND DISPLAY RECEIVER ASSEMBLY - MAP LIGHT ASSEMBLY (TELEPHONE MICROPHONE ASSEMBLY))

(a) Disconnect the F131 radio and display receiver assembly connector.

(b) Disconnect the R2 map light assembly (telephone microphone assembly) connector.

Standard Resistance:

Tester Connection	Condition	Specified Condition
F131-25 (SNS2) - R2-1 (SNS2)	Always	Below 1 Ω
F131-25 (SNS2) - Body ground	Always	10 kΩ or higher

REPAIR OR REPLACE HARNESS OR CONNECTOR

6.	INSPECT DCM (TELEMATICS TRANSCEIVER)

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
F134-35 (MIC-) - Body ground	Always	Below 1 Ω

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

GO TO STEP 8

REPLACE DCM (TELEMATICS TRANSCEIVER)

7.	CHECK HARNESS AND CONNECTOR (RADIO AND DISPLAY RECEIVER ASSEMBLY - MAP LIGHT ASSEMBLY (TELEPHONE MICROPHONE ASSEMBLY))

(a) Disconnect the F131 radio and display receiver assembly connector.

(b) Disconnect the R2 map light assembly (telephone microphone assembly) connector.

Standard Resistance:

Tester Connection	Condition	Specified Condition
F131-25 (SNS2) - R2-1 (SNS2)	Always	Below 1 Ω
F131-22 (MIN-) - R2-7 (MCO-)	Always	Below 1 Ω
F131-25 (SNS2) - Body ground	Always	10 kΩ or higher
F131-22 (MIN-) - Body ground	Always	10 kΩ or higher

REPAIR OR REPLACE HARNESS OR CONNECTOR

8.	INSPECT MAP LIGHT ASSEMBLY (TELEPHONE MICROPHONE ASSEMBLY)

(a) Remove the map light assembly (telephone microphone assembly).

Click here

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

Standard Resistance:

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

*a	Component without harness connected (Map Light Assembly (Telephone Microphone Assembly))

REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY

REPLACE MAP LIGHT ASSEMBLY (TELEPHONE MICROPHONE ASSEMBLY)

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Toyota CH-R Service Manual: Voice Recognition Microphone Disconnected (B1579)

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