Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual: Telematics Transceiver Disconnected (B15DB)

Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual / Audio & Visual & Telematics / Audio / Video / Audio And Visual System (for 8 Inch Display) / Telematics Transceiver Disconnected (B15DB)

DESCRIPTION

If the radio receiver assembly cannot detect the DCM (telematics transceiver) for a certain period of time (90 seconds) after the engine switch is turned on (ACC) and the radio receiver assembly confirms that the information is missing by checking past DCM (telematics transceiver) recognition information (registered information), this DTC will be stored.

The telematics system uses USB communication between devices. If an open, short, short to +B or short to ground occurs in the USB circuit, communication is interrupted and the telematics system will not operate normally.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

B15DB

Telematics Transceiver Disconnected

DCM (telematics transceiver) disconnected
  • Harness or connector
  • DCM (telematics transceiver)
  • Radio receiver assembly

HINT:

This DTC may be stored due to environmental reasons such as electrical noise or interference.

WIRING DIAGRAM

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

  • Inspect the fuses for circuits related to this system before performing the following procedure.
  • Before replacing the DCM (telematics transceiver), refer to Registration.

    Click here

PROCEDURE

1.

CHECK HARNESS AND CONNECTOR (DCM (TELEMATICS TRANSCEIVER) POWER SOURCE)

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

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

J157-20 (E) - Body ground

Always

Below 1 Ω

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

J157-1 (+B) - J157-20 (E)

Always

11 to 14 V

J157-19 (IG2) - J157-20 (E)

Engine switch on (IG)

11 to 14 V
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

2.

INSPECT RADIO RECEIVER ASSEMBLY

(a) Disconnect the J149 radio receiver assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

J149-11 (USBG) - Body ground

Always

Below 1 Ω

*a

Component without harness connected

(Radio Receiver Assembly)

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

J149-10 (USBV) - J149-11 (USBG)

Engine switch on (IG)

4.75 to 5.25 V
NG

REPLACE RADIO RECEIVER ASSEMBLY

OK

3.

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

(a) Disconnect the J149 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

J149-10 (USBV) - J157-15 (USBV)

Always

Below 1 Ω

J149-11 (USBG) - J157-31 (USBG)

Always

Below 1 Ω

J149-10 (USBV) or J157-15 (USBV) - Body ground

Always

10 kΩ or higher

J149-11 (USBG) or J157-31 (USBG) - 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) Check the installation condition.

(1) Check the USB communication lines between the radio receiver assembly and DCM (telematics transceiver) for any installation or connection problems.

(b) Disconnect the J167 radio receiver assembly connector.

(c) Disconnect the J168 DCM (telematics transceiver) connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

J167-1 (USB+) - J168-2 (USB+)

Always

Below 1 Ω

J167-2 (USB-) - J168-1 (USB-)

Always

Below 1 Ω

J167-3 (USBS) - J168-3 (USBS)

Always

Below 1 Ω

J167-1 (USB+) or J168-2 (USB+) - Body ground

Always

10 kΩ or higher

J167-2 (USB-) or J168-1 (USB-) - Body ground

Always

10 kΩ or higher

J167-3 (USBS) or J168-3 (USBS) - Body ground

Always

10 kΩ or higher

*a

Front view of wire harness connector

(to DCM (Telematics Transceiver))

*b

Front view of wire harness connector

(to Radio Receiver Assembly)
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

5.

REPLACE DCM (TELEMATICS TRANSCEIVER)

(a) Replace the DCM (telematics transceiver) with a new one.

Click here

(b) Clear the DTCs.

Body Electrical > Navigation System > Clear DTCs

(c) Turn the engine switch off.

(d) Turn the engine switch on (IG) and wait for 90 seconds.

(e) Recheck for DTCs and check that no DTCs are output.

Body Electrical > Navigation System > Trouble Codes

OK:

No DTCs are output.

OK

END
NG

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