Toyota Camry owners & service manuals

Toyota Camry (XV70): Lost Communication with Wiper ECU LIN (B1245)

Toyota Camry Repair Manual XV70 (2018-2024) / Vehicle Exterior / Wiper / Washer / Wiper And Washer System / Lost Communication with Wiper ECU LIN (B1245)

DESCRIPTION

The main body ECU (multiplex network body ECU) and windshield wiper motor assembly communicate via LIN communication. The main body ECU (multiplex network body ECU) stores this DTC if communication becomes abnormal.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Memory

DTC Output from

B1245

Lost Communication with Wiper ECU LIN

 Detection condition:
  • Battery voltage is 9.5 V or more
Malfunction Status:
  • A communication malfunction between the main body ECU (multiplex network body ECU) and windshield wiper motor assembly
Malfunction Time:
  • 10 seconds or more
  • Windshield wiper motor assembly
  • Main body ECU (multiplex network body ECU)
  • Harness or connector

○

Main Body

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

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

Click here

  • *: w/ Smart Key System

PROCEDURE

1.

CHECK FOR DTC

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream on.

(d) Enter the following menus: Body Electrical / Main Body / Trouble Codes.

(e) Check for DTCs.

Body Electrical > Main Body > Trouble Codes

Result

Proceed to

Only DTC B1245 is output

A

DTC B1245 and B1373 are output

B
B

GO TO B1373

A

2.

CHECK HARNESS AND CONNECTOR (MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) - WINDSHIELD WIPER MOTOR ASSEMBLY)

(a) Disconnect the K51 main body ECU (multiplex network body ECU) connector.

(b) Disconnect the A31 windshield wiper motor assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

K51-3 (LIN3) - A31-2 (LIN)

Always

Below 1 Ω
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

3.

CHECK MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

*a

Component without harness connected

(Main Body ECU (Multiplex Network Body ECU)

(a) Check for pulses according to the value(s) in the table below.

Standard Voltage:

Tester Connection

Condition

Specified Condition

K51-3 (LIN3) - Body ground

Ignition switch off

Below 1 V

Ignition switch ON

Pulse generation
NG

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

OK

4.

CHECK HARNESS AND CONNECTOR (POWER SOURCE - WINDSHIELD WIPER MOTOR ASSEMBLY)

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

A31-4 (+B) - Body ground

Ignition switch ON

11 to 14 V

Less than approximately 60 seconds after ignition switch turned off

11 to 14 V

Approximately 60 seconds after ignition switch turned off

Below 1 V
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

5.

CHECK HARNESS AND CONNECTOR (WINDSHIELD WIPER MOTOR ASSEMBLY - BODY GROUND)

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

A31-1 (GND) - Body ground

Always

Below 1 Ω
OK

REPLACE WINDSHIELD WIPER MOTOR ASSEMBLY

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

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