Toyota Camry owners & service manuals

Toyota Camry (XV70): GSW Terminal Circuit Malfunction (B1243)

Toyota Camry Repair Manual XV70 (2018-2024) / Vehicle Interior / Door Lock / Power Door Lock Control System / GSW Terminal Circuit Malfunction (B1243)

DESCRIPTION

If the collision door lock release function does not operate normally, or an open or short in the GSW input circuit of the main body ECU (multiplex network body ECU) is detected, DTC B1243 will be stored.

HINT:

If DTC B1243 is stored, the automatic door lock function, and collision door lock release function will be prohibited.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

B1243

GSW Terminal Circuit Malfunction

A malfunction occurs in the GSW input circuit of the main body ECU (multiplex network body ECU).
  • Main body ECU (multiplex network body ECU)
  • Airbag sensor assembly
  • Wire harness or connector

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

  • After turning the ignition switch off, waiting time may be required before disconnecting the cable from the negative (-) battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) battery terminal notices before proceeding with work.

    Click here

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

    Click here

    *: w/ Smart Key System

PROCEDURE

1.

CHECK DTC OUTPUT

(a) Clear the DTCs.

Body Electrical > Main Body > Clear DTCs

(b) Recheck for DTCs.

Body Electrical > Main Body > Trouble Codes

OK:

DTC B1243 is not output.

OK

USE SIMULATION METHOD TO CHECK

NG

2.

CHECK MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) (GSW VOLTAGE)

(a) Disconnect the cable from the negative (-) battery terminal.

CAUTION:

Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

NOTICE:

Turning the ignition switch to ON with the airbag sensor assembly connector disconnected causes other DTCs to be stored. Clear the DTCs after performing this inspection.

(b) Disconnect the K73 airbag sensor assembly connector.

(c) Connect the cable to the negative (-) battery terminal.

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

K73-25 (GSW) - Body ground

Ignition switch ON

4.3 to 5.5 V

*a

Front view of wire harness connector

(to Airbag Sensor Assembly)
NG

GO TO STEP 5

OK

3.

REPLACE AIRBAG SENSOR ASSEMBLY

(a) Disconnect the cable from the negative (-) battery terminal.

CAUTION:

Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

(b) Replace the airbag sensor assembly.

Click here

NEXT

4.

CHECK DTC OUTPUT

(a) Clear the DTCs.

Body Electrical > Main Body > Clear DTCs

(b) Recheck for DTCs.

Body Electrical > Main Body > Trouble Codes

OK:

DTC B1243 is not output.

OK

END (AIRBAG SENSOR ASSEMBLY WAS DEFECTIVE)
NG

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

5.

CHECK HARNESS AND CONNECTOR (AIRBAG SENSOR ASSEMBLY - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)

(a) Disconnect the cable from the negative (-) battery terminal.

CAUTION:

Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

(b) Disconnect the 3A instrument panel junction block assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

K73-25 (GSW) - 3A-7

Always

Below 1 ?

3A-7 or K73-25 (GSW) - Body ground

Always

10 k? or higher
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

6.

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).

*a

Component without harness connected

(Instrument Panel Junction Block Assembly)

-

-

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

MB-24 (GSW) - 3A-7

Always

Below 1 ?
OK

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

NG

REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

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