Toyota Corolla Cross Owners & Service Manuals

Toyota Corolla Cross: Lost Communication with Brake System Control Module "A" Missing Message (U012987,U023A87)

Toyota Corolla Cross (2022-2025) Service Manual / Vehicle Interior / Supplemental Restraint Systems / Airbag System / Lost Communication with Brake System Control Module "A" Missing Message (U012987,U023A87)

DESCRIPTION

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Warning Indicate

Test Mode / Check Mode

U012987

Lost Communication with Brake System Control Module "A" Missing Message

Communication stop occurs between the airbag ECU assembly and Skid control ECU (brake actuator assembly) continuously for approximately 2 second or more.

  • CAN communication system
  • Skid control ECU (brake actuator assembly)
  • Airbag ECU assembly

Comes on

Does not apply to test/check mode

U023A87

Lost Communication with Image Processing Module "A" Missing Message

Communication stop occurs between the airbag ECU assembly and forward recognition camera continuously for approximately 10 second or more.

  • CAN communication system
  • Forward recognition camera
  • Airbag ECU assembly

Comes on

Does not apply to test/check mode

PROCEDURE

1.

CHECK DTC OUTPUT

(a) Check for DTCs.

Body Electrical > SRS Airbag > Trouble Codes

Result

Proceed to

U012987 or U023A87 is output

A

DTCs are not output

B

None of the above conditions are met

C

A

GO TO CAN COMMUNICATION SYSTEM

for HEV Model: Click here

for Gasoline Model: Click here

B

USE SIMULATION METHOD TO CHECK

C

GO TO DIAGNOSTIC TROUBLE CODE CHART

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