Lexus RX (RX 350L, RX450h) 2016-2026 Repair Manual: Stereo Component Amplifier Disconnected (B15D3)

Lexus RX (RX 350L, RX450h) 2016-2026 Repair Manual / Audio & Visual & Telematics / Navigation / Multi Info Display / Navigation System / Stereo Component Amplifier Disconnected (B15D3)

DESCRIPTION

The radio receiver assembly and stereo component amplifier assembly are connected via MOST communication lines.

When a MOST communication error occurs between the radio receiver assembly and stereo component amplifier assembly, this DTC will be stored.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

B15D3

Stereo Component Amplifier Disconnected

A device that is listed in the MOST network connected device record of the master unit is missing.
  • Stereo component amplifier assembly power source circuit
  • MOST circuit between radio receiver assembly and stereo component amplifier assembly
  • Stereo component amplifier assembly
  • Radio receiver assembly
  • Harness or connector

HINT:

For the MOST network, the radio receiver assembly is the master unit.

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 Navigation System.

    Click here

  • Inspect the fuses for circuits related to this system before performing the following procedure.

PROCEDURE

1.

CHECK DTC

(a) If DTC B15C3 is output, perform troubleshooting for DTC B15C3 first.

Result

Proceed to

DTC B15C3 is not output.

A

DTC B15C3 is output.

B
B

GO TO DTC B15C3

A

2.

CHECK OPTIONAL COMPONENTS (INCLUDING ASSOCIATED WIRING)

(a) Check that optional components (including associated wiring) which generate radio waves are not installed.

Result

Proceed to

Optional components (including associated wiring) are installed.

A

Optional components (including associated wiring) are not installed.

B

HINT:

  • Electrical noise from radio waves generated by optional components or the wiring for those components may affect MOST communication.
  • This DTC may be stored when a MOST communication error occurs due to electrical noise.
B

GO TO STEP 4

A

3.

REMOVE OPTIONAL COMPONENTS (INCLUDING ASSOCIATED WIRING)

(a) Remove optional components (including associated wiring).

NOTICE:

Do not remove optional components or associated wiring without the permission of the customer.

NEXT

4.

CHECK DTC

(a) Clear the DTCs.

Body Electrical > Navigation System > Clear DTCs

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

Body Electrical > Navigation System > Trouble Codes

OK:

No DTCs are output.

OK

END
NG

5.

CHECK HARNESS AND CONNECTOR (STEREO COMPONENT AMPLIFIER ASSEMBLY POWER SOURCE)

(a) Disconnect the J66 stereo component amplifier assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

J66-3 (GND) - Body ground

Always

Below 1 Ω

J66-18 (GND2) - 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

J66-1 (+B) - J66-3 (GND)

Always

11 to 14 V

J66-16 (+B2) - J66-3 (GND)

Always

11 to 14 V
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

6.

CHECK HARNESS AND CONNECTOR (RADIO RECEIVER ASSEMBLY - STEREO COMPONENT AMPLIFIER ASSEMBLY)

(a) Disconnect the J122 radio receiver assembly connector.

(b) Disconnect the J123 stereo component amplifier assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

J122-5 (MO+) - J123-2 (MI+)

Always

Below 1 Ω

J122-6 (MO-) - J123-3 (MI-)

Always

Below 1 Ω

J122-7 (SLDO) - J123-4 (SLDI)

Always

Below 1 Ω

J122-2 (MI+) - J123-5 (MO+)

Always

Below 1 Ω

J122-3 (MI-) - J123-6 (MO-)

Always

Below 1 Ω

J122-4 (SLDI) - J123-7 (SLDO)

Always

Below 1 Ω

J122-5 (MO+) or J123-2 (MI+) - Body ground

Always

10 kΩ or higher

J122-6 (MO-) or J123-3 (MI-) - Body ground

Always

10 kΩ or higher

J122-7 (SLDO) or J123-4 (SLDI) - Body ground

Always

10 kΩ or higher

J122-2 (MI+) or J123-5 (MO+) - Body ground

Always

10 kΩ or higher

J122-3 (MI-) or J123-6 (MO-) - Body ground

Always

10 kΩ or higher

J122-4 (SLDI) or J123-7 (SLDO) - Body ground

Always

10 kΩ or higher
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

7.

REPLACE STEREO COMPONENT AMPLIFIER ASSEMBLY

(a) Replace the stereo component amplifier assembly with a new or known good one.

Click here

(b) Clear the DTCs.

Body Electrical > Navigation System > Clear DTCs

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

Body Electrical > Navigation System > Trouble Codes

OK:

No DTCs are output.

OK

END
NG

REPLACE RADIO RECEIVER ASSEMBLY

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