NETWORKING: LIN COMMUNICATION SYSTEM (for TMC Made): B278987; ID-BOX Missing Message; 2023 MY Corolla Corolla Hatchback Corolla HV GR Corolla [09/2022

Last Modified: 05-13-2024	6.11:8.1.0	Doc ID: RM1000000026D6H
Model Year Start: 2023	Model: GR Corolla	Prod Date Range: [09/2022 - 11/2022]
Title: NETWORKING: LIN COMMUNICATION SYSTEM (for TMC Made): B278987; ID-BOX Missing Message; 2023 MY Corolla Corolla Hatchback Corolla HV GR Corolla [09/2022 - 11/2022]

DTC

B278987

ID-BOX Missing Message

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	DTC Output from
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.	Certification ECU (smart key ECU assembly) ID code box (immobiliser code ECU) Wire harness or connector	Smart Key

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, perform lock and unlock operations using the door control switch of the multiplex network master switch assembly at intervals of 1.5 seconds or less until communication between the GTS and the vehicle begins, and then select the vehicle model manually.
Then select Model Code "KEY REGIST" under manual mode and enter the following menus: Body Electrical / Smart Key (CAN). While using the GTS, periodically perform lock and unlock operations using the door control switch of the multiplex network master switch assembly 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 HV Model: Click here

for Gasoline Model, except TMMMS Made: Click here

PROCEDURE

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

(a) Disconnect the I167 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	Condition	Specified Condition
I167-8 (LIN) - I20-2 (LIN1)	Ignition switch off	Below 1 Ω
I167-8 (LIN) or I20-2 (LIN1) - Body ground	Ignition switch off	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

Condition

Specified Condition

I20-1 (+B) - Body ground

Always*1

Ignition switch off*2

11 to 14 V

*1: for Gasoline Model
*2: for HV Model

(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).

Click here

4.	REGISTER ECU CODE REGISTRATION

(a) Register the recognition codes in the ECUs.

for HV Model: Click here

for Gasoline Model, except TMMMS Made: Click here

5.	CHECK FOR DTC

(a) Clear the DTCs.

Body Electrical > Smart Key > Clear DTCs

(b) Recheck for DTCs.

Body Electrical > Smart Key > Trouble Codes

OK:

DTC B278987 is not output.

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

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)