DTC C1240: Yaw Rate Sensor discrimination [06/2018 - ]: Procedure

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CHECK PART NUMBER (AIRBAG ECU ASSEMBLY)

Check that the proper yaw rate and acceleration sensor (airbag ECU assembly) is installed.

OK

Proper yaw rate and acceleration sensor (airbag ECU assembly) is installed.

Result

Proceed to
OK
NG

Result:

NG

REPLACE AIRBAG ECU ASSEMBLY. Refer to REMOVAL [06/2018 - 08/2020] , or refer to REMOVAL [08/2020 - 08/2021] , or refer to REMOVAL [08/2021 - 09/2022] , or refer to REMOVAL [09/2022 - ]

Result:

OK

See step 2

RECONFIRM DTC

Clear the DTCs.
Refer to DTC CHECK / CLEAR [06/2018 - ]

Chassis > ABS/VSC/TRAC > Clear DTCs
Turn the power switch off.
Turn the power switch on (IG).

Check if the same DTC is output.

Refer to DTC CHECK / CLEAR [06/2018 - ]

Chassis > ABS/VSC/TRAC > Trouble Codes

Result

Result	Proceed to
DTC C1240 is output.	A
DTC C1240 is not output.	B

Result:

A

REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY. Refer to REMOVAL [06/2018 - 08/2021] , or refer to REMOVAL [08/2021 - 09/2022] , or refer to REMOVAL [09/2022 - ]

Result:

B

USE SIMULATION METHOD TO CHECK. Refer to HOW TO PROCEED WITH TROUBLESHOOTING [06/2018 - ]