Toyota Avalon (XX50): Stereo Component Amplifier Disconnected (B15D3). Telematics Transceiver Disconnected (B15DB). Air Conditioner ECU Vehicle Information Reading/Writing Processor Malfunction (B15F5)

Toyota Avalon (XX50) 2019-2022 Service & Repair Manual / Audio, Visual, Telematics / Navigation / Multi Info Display / Navigation System(for Gasoline Model) / Stereo Component Amplifier Disconnected (B15D3). Telematics Transceiver Disconnected (B15DB). Air Conditioner ECU Vehicle Information Reading/Writing Processor Malfunction (B15F5)

Stereo Component Amplifier Disconnected (B15D3)

DESCRIPTION

The radio and display receiver assembly and stereo component amplifier assembly are connected via AVC-LAN communication line.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area
B15D3	Stereo Component Amplifier Disconnected	When either of the following conditions is met: Stereo component amplifier assembly is/was not connected while the engine switch is/was on (ACC) or on (IG) Communication between the master unit and the stereo component amplifier assembly is not possible when the engine is started.	Stereo component amplifier assembly power source circuit AVC-LAN circuit between radio and display receiver assembly and stereo component amplifier assembly Stereo component amplifier assembly Radio and display receiver assembly Harness or connector

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

B15D3

Stereo Component Amplifier Disconnected

When either of the following conditions is met:

Stereo component amplifier assembly is/was not connected while the engine switch is/was on (ACC) or on (IG)
Communication between the master unit and the stereo component amplifier assembly is not possible when the engine is started.

Stereo component amplifier assembly power source circuit
AVC-LAN circuit between radio and display receiver assembly and stereo component amplifier assembly
Stereo component amplifier assembly
Radio and display receiver assembly
Harness or connector

HINT:

The radio and display receiver assembly is the master unit.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

Inspect the fuses for circuits related to this system before performing the following procedure.
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
When replacing the radio and display receiver assembly, always replace it with a new one. If a radio and display receiver assembly which was installed to another vehicle is used, the following may occur:
- A communication malfunction DTC may be stored.
- The radio and display receiver assembly may not operate normally.

PROCEDURE

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

GO TO DTC B15C3

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 AVC-LAN communication.
This DTC may be stored when an AVC-LAN communication error occurs due to electrical noise.

GO TO STEP 4

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.

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.

END

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

(a) Disconnect the G10 and G8 stereo component amplifier assembly connectors.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
G10-3 (GND) - Body ground	Always	Below 1 Ω
G10-18 (GND2) - Body ground	Always	Below 1 Ω

Standard Voltage:

Tester Connection	Condition	Specified Condition
G10-1 (+B) - G10-3 (GND)	Always	11 to 14 V
G10-16 (+B2) - G10-3 (GND)	Always	11 to 14 V
G8-12 (ACC) - G10-3 (GND)	Engine switch on (ACC)	11 to 14 V

REPAIR OR REPLACE HARNESS OR CONNECTOR

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

(a) Disconnect the G3 radio and display receiver assembly connector.

(b) Disconnect the G8 stereo component amplifier assembly connector.

Standard Resistance:

Tester Connection	Condition	Specified Condition
G3-5 (TX1+) - G8-8 (TX+)	Always	Below 1 Ω
G3-6 (TX1-) - G8-7 (TX-)	Always	Below 1 Ω
G3-5 (TX1+) or G8-8 (TX+) - Body ground	Always	10 kΩ or higher
G3-6 (TX1-) or G8-7 (TX-) - Body ground	Always	10 kΩ or higher

REPAIR OR REPLACE HARNESS OR CONNECTOR

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

Body Electrical > Navigation System > Trouble Codes

OK:

No DTCs are output.

END

REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY

Telematics Transceiver Disconnected (B15DB)

DESCRIPTION

If the radio and display 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 and display 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) DCM (telematics transceiver) power source circuit Radio and display receiver assembly Navigation ECU

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 Navigation System.
Click here
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 may be stored.
- The radio and display receiver assembly or navigation ECU may not operate normally.
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

CHECK DTC

(a) Clear the DTCs.

Body Electrical > Navigation System > Clear DTCs

(b) Turn the engine switch off.

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

Body Electrical > Navigation System > Trouble Codes

OK:

No DTCs are output.

USE SIMULATION METHOD TO CHECK

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

(a) Disconnect the G9 DCM (telematics transceiver) connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
G9-4 (E) - Body ground	Always	Below 1 Ω

Standard Voltage:

Tester Connection	Condition	Specified Condition
G9-1 (+B) - G9-4 (E)	Always	11 to 14 V
G9-8 (ACC) - G9-4 (E)	Engine switch on (ACC)	11 to 14 V
G9-7 (IG2) - G9-4 (E)	Engine switch on (IG)	11 to 14 V

REPAIR OR REPLACE HARNESS OR CONNECTOR

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

(a) Disconnect the G1 radio and display receiver assembly connector.

(b) Disconnect the G11 DCM (telematics transceiver) connector.

Standard Resistance:

Tester Connection	Condition	Specified Condition
G1-10 (USBV) - G11-5 (USBV)	Always	Below 1 Ω
G1-11 (USBG) - G11-3 (USBG)	Always	Below 1 Ω
G1-10 (USBV) or G11-5 (USBV) - Body ground	Always	10 kΩ or higher
G1-11 (USBG) or G11-3 (USBG) - Body ground	Always	10 kΩ or higher

REPAIR OR REPLACE HARNESS OR CONNECTOR

4.	INSPECT RADIO AND DISPLAY RECEIVER ASSEMBLY

(a) Disconnect the G1 radio and display receiver assembly connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
G1-11 (USBG) - Body ground	Always	Below 1 Ω

*a	Component without harness connected (Radio and Display Receiver Assembly)

Standard Voltage:

Tester Connection	Condition	Specified Condition
G1-10 (USBV) - G1-11 (USBG)	Engine switch on (ACC)	4.75 to 5.25 V

REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY

5.	CHECK HARNESS AND CONNECTOR (DCM (TELEMATICS TRANSCEIVER) - NAVIGATION ECU)

(a) Disconnect the G11 DCM (telematics transceiver) connector.

(b) Disconnect the G113 navigation ECU connector.

Standard Resistance:

Tester Connection	Condition	Specified Condition
G11-2 (USB+) - G113-1 (USB+)	Always	Below 1 Ω
G11-1 (USB-) - G113-2 (USB-)	Always	Below 1 Ω
G11-6 (USBS) - G113-3 (USBS)	Always	Below 1 Ω
G11-2 (USB+) or G113-1 (USB+) - Body ground	Always	10 kΩ or higher
G11-1 (USB-) or G113-2 (USB-) - Body ground	Always	10 kΩ or higher
G11-6 (USBS) or G113-3 (USBS) - Body ground	Always	10 kΩ or higher

Front view of wire harness connector

(to DCM (telematics transceiver))

Front view of wire harness connector

(to Navigation ECU)

REPAIR OR REPLACE HARNESS OR CONNECTOR

6.	CHECK 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

(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.

END (DCM (TELEMATICS TRANSCEIVER) IS DEFECTIVE)

7.	CHECK NAVIGATION ECU

(a) Replace the navigation ECU with a new one.

Click here

(b) Clear the DTCs.

Body Electrical > Navigation System > Clear DTCs

(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.

END (NAVIGATION ECU IS DEFECTIVE)

REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY

Air Conditioner ECU Vehicle Information Reading/Writing Processor Malfunction (B15F5)

DESCRIPTION

This DTC is stored when items controlled by the air conditioning amplifier assembly cannot be customized via the navigation system vehicle customization screen.

HINT:

The air conditioning amplifier assembly controls the air conditioning system related items that are customizable via the navigation system vehicle customization screen.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area
B15F5	Air Conditioner ECU Vehicle Information Reading/Writing Processor Malfunction	Air conditioning amplifier assembly vehicle setting processing malfunction	CAN communication system Air conditioning system Air conditioning amplifier assembly Radio and display receiver assembly

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
When replacing the radio and display receiver assembly, always replace it with a new one. If a radio and display receiver assembly which was installed to another vehicle is used, the following may occur:
- A communication malfunction DTC may be stored.
- The radio and display receiver assembly may not operate normally.

PROCEDURE

1.	CHECK CAN COMMUNICATION SYSTEM

(a) Use the Techstream to check if the CAN communication system is functioning normally.

Click here

OK:

CAN communication DTCs are not output.

GO TO CAN COMMUNICATION SYSTEM

2.	CHECK AIR CONDITIONING SYSTEM

(a) Check if the air conditioning system is malfunctioning.

Click here

HINT:

Customization may not be possible depending on the malfunction in the air conditioning system.

OK:

No malfunctions are present in the air conditioning system.

GO TO AIR CONDITIONING SYSTEM

3.	CHECK CUSTOMIZE ITEMS

(a) Make a note of the customizable items for the air conditioning system.

HINT:

The items shown as customizable via the navigation system vehicle customization screen can also be changed using the Techstream. In the following step, the Techstream will be used.

(1) To match-up the items on the navigation system vehicle customization screen with the items on the Techstream, check the customize parameters list for the air conditioning system related items that can be customized via the navigation system vehicle customization screen.

Click here

(b) Using the Techstream, check that it is possible to change the settings of the customize parameters that are available for customization via the navigation system vehicle customization screen.

OK:

The items available for customization via the navigation system vehicle customization screen can be customized successfully using the Techstream.

REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY

REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY

Speaker Output Short (B15C3)

Main Body ECU Vehicle Information Reading/Writing Process Malfunction (B15F6). Certification ECU Vehicle Information Reading/Writing Process Malfunction (B15F7). D-Seat ECU Vehicle Information Reading

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