Toyota Corolla Cross: ID-BOX Missing Message (B278987)

Toyota Corolla Cross (2022-2024) Service Manual / Power Source & Network / Networking / Lin Communication System / ID-BOX Missing Message (B278987)

DESCRIPTION

This DTC is stored when LIN communication between the certification ECU (smart key ECU assembly) and ID code box (immobiliser code ECU) stops for 10 seconds or more.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area
B278987	ID-BOX Missing Message	No communication between certification ECU (smart key ECU assembly) and ID code box (immobiliser code ECU) for 10 seconds or more.	Wire harness or connector ID code box (immobiliser code ECU) Certification ECU (smart key ECU assembly)

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

Inspect the fuses for circuits related to this system before performing the following procedure.
When using the GTS with the ignition switch off, connect the GTS to the DLC3 and turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the GTS and the vehicle begins. Then select Model Code "KEY REGIST" under manual mode and enter the following menus: Body Electrical / Smart Key. While using the GTS, periodically turn a courtesy light switch on and off at intervals of 1.5 seconds or less to maintain communication between the GTS and the vehicle.
If the certification ECU (smart key ECU assembly) or ID code box (immobiliser code ECU) is replaced, refer to Registration.
- for HEV Model: Click here
- for Gasoline Model: Click here

PROCEDURE

1.	CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - ID CODE BOX (IMMOBILISER CODE ECU))

(a) Disconnect the I222 certification ECU (smart key ECU assembly) connector.

(b) Disconnect the I20 ID code box (immobiliser code ECU) connector.

NOTICE:

Make sure that each ECU is in sleep mode before performing the inspection. To enter sleep mode, turn the ignition switch from ON to off and wait for 180 seconds or more without operating any switches.

Standard Resistance:

Tester Connection	Switch Condition	Specified Condition
I222-8 (LIN) - I20-2 (LIN1)	Ignition switch off	Below 1 Ω
I222-8 (LIN) - Body ground	Always	10 kΩ or higher
I20-2 (LIN1) - Body ground	Always	10 kΩ or higher

REPAIR OR REPLACE HARNESS OR CONNECTOR

2.	CHECK HARNESS AND CONNECTOR (ID CODE BOX (IMMOBILISER CODE ECU) - AUXILIARY BATTERY AND BODY GROUND)

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

Standard Voltage:

Tester Connection	Switch Condition	Specified Condition
I20-1 (+B) -I20-5 (GND)	Ignition switch off	11 to 14 V

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
I20-5 (GND) - Body ground	Always	Below 1 Ω

REPAIR OR REPLACE HARNESS OR CONNECTOR

3.	REPLACE ID CODE BOX (IMMOBILISER CODE ECU)

(a) Replace the ID code box (immobiliser code ECU).

HINT:

Click here

4.	REGISTER ECU CODE REGISTRATION

(a) Register the recognition codes in the ECUs.

for HEV Model: Click here
for Gasoline Model:: Click here

CLEAR DTC

(a) Clear the DTCs.

Body Electrical > Smart Key > Clear DTCs

6.	CHECK FOR DTC

(a) Check for DTCs.

Body Electrical > Smart Key > Trouble Codes

Result	Proceed to
B278987 is not output	A
B278987 is output	B

END (ID CODE BOX (IMMOBILISER CODE ECU) WAS DEFECTIVE)

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

SEE MORE:

Removal

REMOVAL CAUTION / NOTICE / HINT COMPONENTS (REMOVAL) Procedure Part Name Code 1 MASS AIR FLOW METER SUB-ASSEMBLY 22204 - - The necessary procedures (adjustment, calibration, initialization or registration) that must be performed afte

Removal

REMOVAL CAUTION / NOTICE / HINT COMPONENTS (REMOVAL) Procedure Part Name Code 1 STEERING WHEEL POSITION - - - 2 LOWER STEERING COLUMN COVER 45287 - - 3 UPPER STEERING COLUMN COVER 45286B - - -

Toyota Corolla Cross: ID-BOX Missing Message (B278987)

READ NEXT:

Power Source Control System Missing Message (B278C87)

Network Gateway Ecu

Removal

SEE MORE:

Removal

Removal