Last Modified: 05-13-2024 6.11:8.1.0 Doc ID: RM1000000028KBY
Model Year Start: 2023 Model: GR Corolla Prod Date Range: [09/2022 - 11/2022]
Title: THEFT DETERRENT / KEYLESS ENTRY: IMMOBILISER SYSTEM (w/o Smart Key System): B279A12,B279A; Engine Immobiliser System Circuit Short to Battery; 2023 MY Corolla Corolla Hatchback Corolla HV GR Corolla [09/2022 - 11/2022]

DTC

B279A12

Engine Immobiliser System Circuit Short to Battery

DTC

B279A

Theft Deterrent System Communication Line High Fixation

DESCRIPTION

  • If the communication line (EFIO-IMI) to the transponder key ECU assembly is stuck high (e.g. shorted to +B), the hybrid vehicle control ECU stores this DTC.*1
  • If the communication line (EFIO-IMI) to the transponder key ECU assembly is stuck high (e.g. shorted to +B), the ECM stores this DTC.*2
    • *1: for HV Model
    • *2: for Gasoline Model

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Note

B279A

Theft Deterrent System Communication Line High Fixation

Communication line (EFIO-IMI) between the ECM and transponder key ECU assembly is stuck high.
  • Wire harness or connector
  • ECM
  • Transponder key ECU assembly

DTC Output Confirmation Operation:

  • Turn the ignition switch to ON and wait 6 seconds.

B279A12

Engine Immobiliser System Circuit Short to Battery
  • Communication line (EFIO-IMI) between the hybrid vehicle control ECU and transponder key ECU assembly is stuck high.*1
  • Communication line (EFIO-IMI) between the ECM and transponder key ECU assembly is stuck high.*2
  • Wire harness or connector
  • Hybrid vehicle control ECU*1
  • ECM*2
  • Transponder key ECU assembly

DTC Output Confirmation Operation:

  • Turn the ignition switch to ON and wait 6 seconds.
  • *1: for HV Model
  • *2: for Gasoline Model

Vehicle Condition and Fail-safe Operation when Malfunction Detected

Vehicle Condition when Malfunction Detected

Fail-safe Operation when Malfunction Detected
  • Hybrid vehicle control ECU cannot be started (initial ignition occurs and hybrid vehicle control ECU cranks, then ignition stops)*1
  • Engine cannot be started (initial ignition occurs and engine cranks, then ignition stops)*2
  • Hybrid vehicle control ECU cannot be started*1
  • Engine cannot be started*2
  • *1: for HV Model
  • *2: for Gasoline Model

Related Data List and Active Test

DTC No.

Data List and Active Test

B279A*1

-

B279A12*2*3

-
  • *1: for 2ZR-FAE
  • *2: for M20A-FKS
  • *3: for 2ZR-FXE

WIRING DIAGRAM

for HV Model

for Gasoline Model

CAUTION / NOTICE / HINT

NOTICE:

  • If the transponder key ECU assembly or hybrid vehicle control ECU is replaced, refer to Registration.*1

    If the transponder key ECU assembly or ECM is replaced, refer to Registration.*2

    Click here 2023 MY Corolla Corolla Hatchback Corolla HV GR Corolla [09/2022 - 11/2022]; THEFT DETERRENT / KEYLESS ENTRY: IMMOBILISER SYSTEM (w/o Smart Key System): REGISTRATION

  • After repair, confirm that no DTCs are output by performing "DTC Output Confirmation Operation".
    • *1: for HV Model
    • *2: for Gasoline Model

PROCEDURE

1.

SYSTEM CHECK

(a) Check the vehicle specification.

Result

Proceed to

for HV Model

A

for Gasoline Model

B
B

GO TO STEP 6

A

2.

CHECK CONNECTION OF CONNECTOR

(a) Check that the connectors are properly connected to the hybrid vehicle control ECU and transponder key ECU assembly.

OK:

Connectors are properly connected.

NG

CONNECT CONNECTORS PROPERLY
OK

3.

CHECK HYBRID VEHICLE CONTROL ECU

(a) Disconnect the I67 transponder key ECU assembly connector.

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

I67-11 (EFIO) - Body ground

Ignition switch off

11 to 14 V
NG

GO TO STEP 5

OK

4.

CHECK HYBRID VEHICLE CONTROL ECU (TERMINAL IMI)

(a) Connect the I67 transponder key ECU assembly connector.

(b) Using an oscilloscope, check the waveform.

*a

Component with harness connected

(Hybrid Vehicle Control ECU)

*b

Waveform

*c

Approximately 160 ms.

*d

Approximately 270 ms.

OK:

Tester Connection

Condition

Tool Setting

Specified Condition

I3-53 (IMI) - Body ground

Within 3 seconds of starter operation and initial combustion, or within 3 seconds of ignition switch first being turned to ON after cable disconnected and reconnected to negative (-) auxiliary battery terminal

2 V/DIV., 500 ms./DIV.

Pulse generation

(See waveform)
OK

REPLACE HYBRID VEHICLE CONTROL ECU

NG

REPLACE TRANSPONDER KEY ECU ASSEMBLY

5.

CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY ECU ASSEMBLY - HYBRID VEHICLE CONTROL ECU)

(a) Disconnect the I3 hybrid vehicle control ECU connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

I67-11 (EFIO) - I3-53 (IMI)

Always

Below 1 Ω

I67-11 (EFIO) or I3-53 (IMI) - Other terminals and body ground

Always

10 kΩ or higher
OK

REPLACE HYBRID VEHICLE CONTROL ECU

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

6.

CHECK CONNECTION OF CONNECTOR

(a) Check that the connectors are properly connected to the ECM and transponder key ECU assembly.

OK:

Connectors are properly connected.

NG

CONNECT CONNECTORS PROPERLY
OK

7.

CHECK ECM

(a) Disconnect the I67 transponder key ECU assembly connector.

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

I67-11 (EFIO) - Body ground

Always

11 to 14 V
NG

GO TO STEP 9

OK

8.

CHECK TRANSPONDER KEY ECU ASSEMBLY (TERMINAL EFIO)

(a) Connect the I67 transponder key ECU assembly connector.

(b) Using an oscilloscope, check the waveform.

*a

Component with harness connected

(Transponder Key ECU Assembly)

*b

Waveform

*c

Approximately 160 ms.

*d

Approximately 270 ms.

OK:

Tester Connection

Condition

Tool Setting

Specified Condition

I67-11 (EFIO) - Body ground

Within 3 seconds of starter operation and initial combustion, or within 3 seconds of ignition switch first being turned to ON after cable disconnected and reconnected to negative (-) auxiliary battery terminal

2 V/DIV., 500 ms./DIV.

Pulse generation

(See waveform)
OK

REPLACE ECM

for M20A-FKS: Click here 2023 MY Corolla Corolla Hatchback [09/2022 - 11/2022]; M20A-FKS (ENGINE CONTROL): ECM: REMOVAL

for 2ZR-FAE: Click here 2023 MY Corolla [09/2022 - 11/2022]; 2ZR-FAE (ENGINE CONTROL): ECM: REMOVAL

NG

REPLACE TRANSPONDER KEY ECU ASSEMBLY

9.

CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY ECU ASSEMBLY - ECM)

(a) Disconnect the A46*1 or A47*2 ECM connector.

  • *1: for 2ZR-FAE
  • *2: for M20A-FKS

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

Standard Resistance:

for 2ZR-FAE

Tester Connection

Condition

Specified Condition

I67-11 (EFIO) - A46-28 (IMI)

Always

Below 1 Ω

I67-11 (EFIO) or A46-28 (IMI) - Other terminals and body ground

Always

10 kΩ or higher

for M20A-FKS

Tester Connection

Condition

Specified Condition

I67-11 (EFIO) - A47-26 (IMI)

Always

Below 1 Ω

I67-11 (EFIO) or A47-26 (IMI) - Other terminals and body ground

Always

10 kΩ or higher
OK

REPLACE ECM

for M20A-FKS: Click here 2023 MY Corolla Corolla Hatchback [09/2022 - 11/2022]; M20A-FKS (ENGINE CONTROL): ECM: REMOVAL

for 2ZR-FAE: Click here 2023 MY Corolla [09/2022 - 11/2022]; 2ZR-FAE (ENGINE CONTROL): ECM: REMOVAL

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR