Lexus ES: LIN Communication Bus Malfunction (B2325)

DESCRIPTION

If the main body ECU (multiplex network body ECU) detects a communication error with an ECU connected to the door bus lines for 8 seconds or more, DTC B2325 will be stored.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area
B2325	LIN Communication Bus Malfunction	The main body ECU (multiplex network body ECU) detects a communication error with an ECU connected to the door bus lines for 8 seconds or more.	Main body ECU (multiplex network body ECU) Instrument panel junction block assembly Multiplex network master switch assembly Power window regulator motor assembly (driver door) Power window regulator motor assembly (front passenger door) Power window regulator motor assembly (rear LH door) Power window regulator motor assembly (rear RH door) Sliding roof ECU (sliding roof drive gear sub-assembly) Kick door control sensor* Wire harness or connector

WIRING DIAGRAM

CAUTION / NOTICE / HINT

PROCEDURE

1.	CHECK POWER WINDOW REGULATOR MOTOR ASSEMBLY (DRIVER DOOR)

(a) Disconnect the J27 power window regulator motor assembly (driver door) connector.

(b) Clear the DTCs.

Body Electrical > Main Body > Clear DTCs

(c) After 8 seconds have elapsed, check if the DTC is output.

Body Electrical > Main Body > Trouble Codes

Result	Proceed to
DTC B2325 is output	A
DTC B2325 is not output	B

B

REPLACE POWER WINDOW REGULATOR MOTOR ASSEMBLY (DRIVER DOOR)

A

2.	CHECK MULTIPLEX NETWORK MASTER SWITCH ASSEMBLY

(a) Disconnect the J20 multiplex network master switch assembly connector.

(b) Clear the DTCs.

Body Electrical > Main Body > Clear DTCs

(c) After 10 seconds have elapsed, check if the DTC is output.

Body Electrical > Main Body > Trouble Codes

Result	Proceed to
DTC B2325 is output	A
DTC B2325 is not output	B

B

REPLACE MULTIPLEX NETWORK MASTER SWITCH ASSEMBLY

A

3.	CHECK POWER WINDOW REGULATOR MOTOR ASSEMBLY (FRONT PASSENGER DOOR)

(a) Disconnect the J5 power window regulator motor assembly (front passenger door) connector.

(b) Clear the DTCs.

Body Electrical > Main Body > Clear DTCs

(c) After 10 seconds have elapsed, check if the DTC is output.

Body Electrical > Main Body > Trouble Codes

Result	Proceed to
DTC B2325 is output	A
DTC B2325 is not output	B

B

REPLACE POWER WINDOW REGULATOR MOTOR ASSEMBLY (FRONT PASSENGER DOOR)

A

4.	CHECK POWER WINDOW REGULATOR MOTOR ASSEMBLY (REAR RH DOOR)

(a) Disconnect the L4 power window regulator motor assembly (rear RH door) connector.

(b) Clear the DTCs.

Body Electrical > Main Body > Clear DTCs

(c) After 10 seconds have elapsed, check if the DTC is output.

Body Electrical > Main Body > Trouble Codes

Result	Proceed to
DTC B2325 is output	A
DTC B2325 is not output	B

B

REPLACE POWER WINDOW REGULATOR MOTOR ASSEMBLY (REAR RH DOOR)

A

5.	CHECK POWER WINDOW REGULATOR MOTOR ASSEMBLY (REAR LH DOOR)

(a) Disconnect the L10 power window regulator motor assembly (rear LH door) connector.

(b) Clear the DTCs.

Body Electrical > Main Body > Clear DTCs

(c) After 10 seconds have elapsed, check if the DTC is output.

Body Electrical > Main Body > Trouble Codes

Result	Proceed to
DTC B2325 is output*1	A
DTC B2325 is output*2	B
DTC B2325 is not output	C

B

GO TO STEP 7

C

REPLACE POWER WINDOW REGULATOR MOTOR ASSEMBLY (REAR LH DOOR)

A

6.	CHECK KICK DOOR CONTROL SENSOR

(a) Disconnect the S5 kick door control sensor connector.

(b) Clear the DTCs.

Body Electrical > Main Body > Clear DTCs

(c) After 10 seconds have elapsed, check if the DTC is output.

Body Electrical > Main Body > Trouble Codes

Result	Proceed to
DTC B2325 is output	A
DTC B2325 is not output	B

B

REPLACE KICK DOOR CONTROL SENSOR

A

7.	CHECK SLIDING ROOF ECU (SLIDING ROOF DRIVE GEAR SUB-ASSEMBLY)

(a) Disconnect the P22 sliding roof ECU (sliding roof drive gear sub-assembly) connector.

(b) Clear the DTCs.

Body Electrical > Main Body > Clear DTCs

(c) After 10 seconds have elapsed, check if the DTC is output.

Body Electrical > Main Body > Trouble Codes

Result	Proceed to
DTC B2325 is output	A
DTC B2325 is not output	B

B

REPLACE SLIDING ROOF ECU (SLIDING ROOF DRIVE GEAR SUB-ASSEMBLY)

A

8.	CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - EACH ECU)

(a) Disconnect the 3H instrument panel junction block assembly connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
3H-25 - Body ground	Always	10 kΩ or higher

(c) Disconnect all other connectors in the same circuit.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
3H-25 - Other terminals	Always	10 kΩ or higher

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

9.	CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - SLIDING ROOF ECU (SLIDING ROOF DRIVE GEAR SUB-ASSEMBLY))

(a) Disconnect the 3D instrument panel junction block assembly connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
3D-17 - Body ground	Always	10 kΩ or higher
3D-17 - Other terminals	Always	10 kΩ or higher

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

10.	INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

(a) Remove the instrument panel junction block assembly.

Click here

(b) Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.

*a

Component without harness connected (Instrument Panel Junction Block Assembly)

-

-

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

HINT:

This inspection is to check the LIN communication line in the instrument panel junction block assembly that connects the wire harness to the built-in main body ECU (multiplex network body ECU).

Standard Resistance:

Tester Connection	Condition	Specified Condition
3H-25 - 3D-3	Always	10 kΩ or higher
MB-16 (LIN2) - Other terminals	Always	10 kΩ or higher

NG

REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

OK

11.	INSPECT MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

(a) Install the main body ECU (multiplex network body ECU) to the instrument panel junction block assembly.

Click here

(b) Install the instrument panel junction block assembly.

*a

Component with harness connected (Instrument Panel Junction Block Assembly)

*b

Waveform

(c) Using a Techstream, check the waveform.

HINT:

This inspection is to check the LIN communication line in the instrument panel junction block assembly that connects the wire harness to the built-in main body ECU (multiplex network body ECU).

OK:

Tester Connection	Condition	Tool Setting	Specified Condition
3H-25 - Body ground	Power switch on (IG)	2 V/DIV., 200 ms/DIV.	Pulse generation (See waveform)
3D-17 - Body ground	Power switch on (IG)	2 V/DIV., 200 ms/DIV.	Pulse generation (See waveform)

OK

USE SIMULATION METHOD TO CHECK

NG

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

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