Lexus RX (RX 350L, RX450h) 2016-2026 Repair Manual: Voice Recognition Microphone Disconnected (B1579)

Lexus RX (RX 350L, RX450h) 2016-2026 Repair Manual / Audio & Visual & Telematics / Audio / Video / Audio And Visual System (for 8 Inch Display) / Voice Recognition Microphone Disconnected (B1579)

DESCRIPTION

The radio receiver 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.
  • Telephone microphone assembly
  • DCM (telematics transceiver)*
  • Radio receiver assembly
  • Harness or connector
  • *: w/ Manual (SOS) Switch

WIRING DIAGRAM

w/ Manual (SOS) Switch w/o Manual (SOS) Switch

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

  • Before replacing the DCM (telematics transceiver), refer to Registration.

    Click here

PROCEDURE

1.

INSPECT RADIO RECEIVER ASSEMBLY

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

J151-22 (MIN-) - Body ground

Always

Below 1 Ω

*a

Component with harness connected

(Radio Receiver Assembly)
NG

REPLACE RADIO RECEIVER ASSEMBLY

OK

2.

CHECK MODEL

(a) Choose the model to be inspected.

Result

Proceed to

w/ Manual (SOS) Switch

A

w/o Manual (SOS) Switch

B
B

GO TO STEP 8

A

3.

CHECK HARNESS AND CONNECTOR (DCM (TELEMATICS TRANSCEIVER) - TELEPHONE MICROPHONE ASSEMBLY)

(a) Disconnect the J157 DCM (telematics transceiver) connector.

(b) Disconnect the U15 telephone microphone assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

J157-7 (MCI-) - U15-4 (MCO-)

Always

Below 1 Ω

J157-7 (MCI-) or U15-4 (MCO-) - Body ground

Always

10 kΩ or higher
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

4.

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

(a) Disconnect the J151 radio receiver assembly connector.

(b) Disconnect the J157 DCM (telematics transceiver) connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

J151-22 (MIN-) - J157-32 (MCO-)

Always

Below 1 Ω

J151-22 (MIN-) or J157-32 (MCO-) - Body ground

Always

10 kΩ or higher
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

5.

CHECK HARNESS AND CONNECTOR (RADIO RECEIVER ASSEMBLY - TELEPHONE MICROPHONE ASSEMBLY)

(a) Disconnect the J151 radio receiver assembly connector.

(b) Disconnect the U15 telephone microphone assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

J151-25 (SNS2) - U15-3 (SNS2)

Always

Below 1 Ω

J151-25 (SNS2) or U15-3 (SNS2) - Body ground

Always

10 kΩ or higher
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

6.

INSPECT DCM (TELEMATICS TRANSCEIVER)

(a) Reconnect the J157 DCM (telematics transceiver) connector.

(b) Reconnect the J151 radio receiver assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

J157-7 (MCI-) - Body ground

Always

Below 1 Ω

*a

Component with harness connected

(DCM (Telematics Transceiver))

(d) Proceed to the next step based on the inspection result.

NG

REPLACE DCM (TELEMATICS TRANSCEIVER)

OK

7.

INSPECT TELEPHONE MICROPHONE ASSEMBLY

(a) Remove the 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

3 (SNS2) - 4 (MCO-)

Always

Below 1 Ω

*a

Component without harness connected

(Telephone Microphone Assembly)
OK

REPLACE RADIO RECEIVER ASSEMBLY

NG

REPLACE TELEPHONE MICROPHONE ASSEMBLY

8.

CHECK HARNESS AND CONNECTOR (RADIO RECEIVER ASSEMBLY - TELEPHONE MICROPHONE ASSEMBLY)

(a) Disconnect the J151 radio receiver assembly connector.

(b) Disconnect the U15 telephone microphone assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

J151-25 (SNS2) - U15-3 (SNS2)

Always

Below 1 Ω

J151-22 (MIN-) - U15-4 (MCO-)

Always

Below 1 Ω

J151-25 (SNS2) or U15-3 (SNS2) - Body ground

Always

10 kΩ or higher

J151-22 (MIN-) or U15-4 (MCO-) - Body ground

Always

10 kΩ or higher
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

9.

INSPECT TELEPHONE MICROPHONE ASSEMBLY

(a) Remove the 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

3 (SNS2) - 4 (MCO-)

Always

Below 1 Ω

*a

Component without harness connected

(Telephone Microphone Assembly)
OK

REPLACE RADIO RECEIVER ASSEMBLY

NG

REPLACE TELEPHONE MICROPHONE ASSEMBLY

    GVIF Disconnected (from EMV/MM Integrated Device to Multi Display) (B1575)
    DESCRIPTION The radio receiver assembly and multi-display assembly are connected via video signal (digital) lines. This DTC is stored when a video signal (digital) line is disconnected. DTC No. D ...

    USB Device Malfunction (B1585)
    DESCRIPTION This DTC is stored when a malfunction occurs in a connected device. DTC No. Detection Item DTC Detection Condition Trouble Area B1585 USB Device Malfunction When any of th ...

    Other materials:

    Lexus RX (RX 350L, RX450h) 2016-2026 Repair Manual > Steering Lock System: Open / Short in Steering Lock ECU (B2781)
    DESCRIPTION The steering lock ECU and steering lock motor are built into the steering lock actuator or upper bracket assembly. The steering lock ECU (steering lock actuator or upper bracket assembly) detects whether the steering lock is in the lock or unlock position by using the lock sensor and unl ...

    Lexus RX (RX 350L, RX450h) 2016-2026 Repair Manual > Ambient Light(for Front Door): Inspection
    INSPECTION PROCEDURE 1. INSPECT FRONT DOOR TRIM BOARD SUBASSEMBLY LH (FRONT DOOR AMBIENT ILLUMINATION LIGHT LH) (a) Apply battery voltage to the connector and check that the front door ambient illumination light LH comes on. OK: Measurement Condition Condition Specified Condition Batt ...

    Lexus RX (RX 350L, RX450h) 2016-{YEAR} Owners Manual

    Lexus RX (RX 350L, RX450h) 2016-{YEAR} Repair Manual

    © 2026 Copyright www.lexusrx.net
    0.0116