Last Modified: 07-31-2024 6.11:8.1.0 Doc ID: RM100000001H6I0
Model Year Start: 2020 Model: Corolla Prod Date Range: [01/2019 - 09/2022]
Title: NETWORKING: LIN COMMUNICATION SYSTEM (for HV Model): B2325; LIN Communication Bus Malfunction; 2020 - 2022 MY Corolla Corolla HV [01/2019 - 09/2022]

DTC

B2325

LIN Communication Bus Malfunction

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)
  • Wire harness or connector

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

  • When a power window regulator motor assembly is replaced or removed and reinstalled, it is necessary to perform initialization.

    Click here 2020 - 2022 MY Corolla Corolla HV [01/2019 - 09/2022]; WINDOW / GLASS: POWER WINDOW CONTROL SYSTEM (for HV Model): INITIALIZATION

  • Before replacing the main body ECU (multiplex network body ECU), refer to Registration.

    Click here 2020 MY Corolla Corolla HV [01/2019 - 04/2020]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, HV Model): REGISTRATION 2021 - 2022 MY Corolla Corolla HV [04/2020 - 09/2022]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, HV Model): REGISTRATION

PROCEDURE

1.

CHECK POWER WINDOW REGULATOR MOTOR ASSEMBLY (DRIVER DOOR)

(a) Disconnect the L2 power window regulator motor assembly (driver door) connector.

(b) Clear the DTCs.

Body Electrical > Main Body > Clear DTCs

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

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) 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 03/2019]; WINDOW / GLASS: POWER WINDOW REGULATOR MOTOR (for Front Door): REMOVAL 2020 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [03/2019 - 09/2022]; WINDOW / GLASS: POWER WINDOW REGULATOR MOTOR (for Front Door): REMOVAL

A

2.

CHECK MULTIPLEX NETWORK MASTER SWITCH ASSEMBLY

(a) Disconnect the L7 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 same DTC is output again.

Body Electrical > Main Body > Trouble Codes

Result

Proceed to

DTC B2325 is output

A

DTC B2325 is not output

B
B

GO TO STEP 9

A

3.

CHECK POWER WINDOW REGULATOR MOTOR ASSEMBLY (FRONT PASSENGER DOOR)

(a) Disconnect the K2 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 same DTC is output again.

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 M2 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 same DTC is output again.

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) 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 03/2019]; WINDOW / GLASS: POWER WINDOW REGULATOR MOTOR (for Rear Door): REMOVAL 2020 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [03/2019 - 09/2022]; WINDOW / GLASS: POWER WINDOW REGULATOR MOTOR (for Rear Door): REMOVAL

A

5.

CHECK POWER WINDOW REGULATOR MOTOR ASSEMBLY (REAR LH DOOR)

(a) Disconnect the N2 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 same DTC is output again.

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 LH DOOR) 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 03/2019]; WINDOW / GLASS: POWER WINDOW REGULATOR MOTOR (for Rear Door): REMOVAL 2020 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [03/2019 - 09/2022]; WINDOW / GLASS: POWER WINDOW REGULATOR MOTOR (for Rear Door): REMOVAL

A

6.

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

(a) Disconnect the 4A 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

4A-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

4A-25 - Other terminals

Always

10 kΩ or higher
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

7.

INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

(a) Remove the instrument panel junction block assembly.

Click here 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 03/2019]; POWER DISTRIBUTION: MAIN BODY ECU: REMOVAL 2020 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [03/2019 - 09/2022]; POWER DISTRIBUTION: MAIN BODY ECU: REMOVAL

(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

MB-16 (LIN2) - Other terminals

Always

10 kΩ or higher
NG

REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 03/2019]; POWER DISTRIBUTION: MAIN BODY ECU: REMOVAL 2020 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [03/2019 - 09/2022]; POWER DISTRIBUTION: MAIN BODY ECU: REMOVAL

OK

8.

CHECK MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

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

(b) Connect all instrument panel junction block assembly connectors other than 4F and 4A.

*a

Component without 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

4A-25 - 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) 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 03/2019]; POWER DISTRIBUTION: MAIN BODY ECU: REMOVAL 2020 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [03/2019 - 09/2022]; POWER DISTRIBUTION: MAIN BODY ECU: REMOVAL

9.

CHECK HARNESS AND CONNECTOR (MULTIPLEX NETWORK MASTER SWITCH ASSEMBLY - POWER WINDOW REGULATOR MOTOR ASSEMBLY (DRIVER DOOR))

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

L7-16 (LIN2) - Body ground

Always

10 kΩ or higher

L7-16 (LIN2) - Other terminals

Always

10 kΩ or higher
OK

REPLACE MULTIPLEX NETWORK MASTER SWITCH ASSEMBLY

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR