Last Modified: 07-31-2024 6.11:8.1.0 Doc ID: RM100000001GV8E
Model Year Start: 2020 Model: GR Corolla Prod Date Range: [01/2019 - 11/2022]
Title: THEFT DETERRENT / KEYLESS ENTRY: IMMOBILISER SYSTEM (w/o Smart Key System): B279986,B2799; Engine Immobiliser System Signal (Some Circuit Quantity, Reported via Serial Data) Invalid; 2020 - 2023 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 11/2022]

DTC

B279986

Engine Immobiliser System Signal (Some Circuit Quantity, Reported via Serial Data) Invalid

DTC

B2799

Engine Immobiliser System Malfunction

DESCRIPTION

The ECM stores this DTC when a communication line between the ECM and transponder key ECU assembly is malfunctioning or the communication ID of the ECM and transponder key ECU assembly do not match.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Note

B2799

Engine Immobiliser System Malfunction

One of the following conditions is met:

  • Error in communication between ECM and transponder key ECU assembly.
  • Error in communication lines.
  • Communication ID is different during communication between ECM and transponder key ECU assembly.
  • Wire harness or connector
  • Transponder key ECU assembly
  • ECM

DTC Output Confirmation Operation:

  • Start the engine and wait 10 seconds.
  • After disconnecting and reconnecting the cable to the negative (-) battery terminal, turn the ignition switch to ON and wait 10 seconds.

B279986

Engine Immobiliser System Signal (Some Circuit Quantity, Reported via Serial Data) Invalid

One of the following conditions is met:

  • Error in communication between ECM and transponder key ECU assembly.
  • Error in communication lines.
  • Communication ID is different during communication between ECM and transponder key ECU assembly.
  • Wire harness or connector
  • Transponder key ECU assembly
  • ECM

DTC Output Confirmation Operation:

  • Start the engine and wait 10 seconds.
  • After disconnecting and reconnecting the cable to the negative (-) battery terminal, turn the ignition switch to ON and wait 10 seconds.

Vehicle Condition and Fail-safe Operation when Malfunction Detected

Vehicle Condition when Malfunction Detected

Fail-safe Operation when Malfunction Detected

Engine cannot be started

-

Related Data List and Active Test

DTC No.

Data List and Active Test

B2799*1

-

B279986*2

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

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

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

    Click here 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 09/2019]; THEFT DETERRENT / KEYLESS ENTRY: IMMOBILISER SYSTEM (w/o Smart Key System): REGISTRATION 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [09/2019 - 04/2020]; THEFT DETERRENT / KEYLESS ENTRY: IMMOBILISER SYSTEM (w/o Smart Key System): REGISTRATION 2021 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [04/2020 - 09/2022]; THEFT DETERRENT / KEYLESS ENTRY: IMMOBILISER SYSTEM (w/o Smart Key System): REGISTRATION 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".

HINT:

If transponder key ECU assembly DTCs are output simultaneously, troubleshoot the transponder key ECU assembly DTCs first.

PROCEDURE

1.

REGISTER ECU COMMUNICATION ID

(a) Reregister the ECU communication ID.

NEXT

2.

INSPECT TRANSPONDER KEY ECU ASSEMBLY (TERMINAL EFII)

(a) 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

I67-10 (EFII) - 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 (-) battery terminal

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

Pulse generation

(See waveform)

OK:

Waveform is similar to that shown in the illustration.

Result

Proceed to

OK

A

NG (Terminal EFII stuck low (2.4 V or less))

B

NG (Terminal EFII stuck high (12 V) or abnormal waveform)

C
B

GO TO STEP 7

C

GO TO STEP 9

A

3.

INSPECT TRANSPONDER KEY ECU ASSEMBLY (TERMINAL EFIO)

(a) 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 (-) battery terminal

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

Pulse generation

(See waveform)

OK:

Waveform is similar to that shown in the illustration.

NG

GO TO STEP 6

OK

4.

REGISTER ECU COMMUNICATION ID

(a) Reregister the ECU communication ID.

NEXT

5.

CHECK WHETHER ENGINE STARTS

(a) Using a registered door control transmitter assembly, turn the ignition switch to ON.

(b) Check that the engine starts 5 seconds after the ignition switch was turned to ON.

OK:

Engine starts normally.

OK

END (COMMUNICATION ID REGISTRATION WAS DEFECTIVE)
NG

REPLACE ECM

for M20A-FKS: Click here 2020 MY Corolla Corolla Hatchback [01/2019 - 03/2019]; M20A-FKS (ENGINE CONTROL): ECM: REMOVAL 2020 - 2022 MY Corolla Corolla Hatchback [03/2019 - 09/2022]; M20A-FKS (ENGINE CONTROL): ECM: REMOVAL 2023 MY Corolla Corolla Hatchback [09/2022 - 11/2022]; M20A-FKS (ENGINE CONTROL): ECM: REMOVAL

for 2ZR-FAE: Click here 2020 MY Corolla [01/2019 - 03/2019]; 2ZR-FAE (ENGINE CONTROL): ECM: REMOVAL 2020 - 2022 MY Corolla [03/2019 - 09/2022]; 2ZR-FAE (ENGINE CONTROL): ECM: REMOVAL 2023 MY Corolla [09/2022 - 11/2022]; 2ZR-FAE (ENGINE CONTROL): ECM: REMOVAL

6.

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

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

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

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

(c) 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 TRANSPONDER KEY ECU ASSEMBLY 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 03/2019]; THEFT DETERRENT / KEYLESS ENTRY: TRANSPONDER KEY ECU: REMOVAL 2020 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [03/2019 - 09/2022]; THEFT DETERRENT / KEYLESS ENTRY: TRANSPONDER KEY ECU: REMOVAL 2023 MY Corolla Corolla Hatchback Corolla HV GR Corolla [09/2022 - 11/2022]; THEFT DETERRENT / KEYLESS ENTRY: TRANSPONDER KEY ECU: REMOVAL

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

7.

INSPECT ECM (IMO TERMINAL VOLTAGE)

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

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

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

Standard Voltage:

for 2ZR-FAE

Tester Connection

Condition

Result

A46-45 (IMO) - Body ground

Ignition switch turned to ON using registered door control transmitter assembly

Terminal IMO stuck low (2.4 V or less)

Terminal IMO stuck high (12 V) or abnormal waveform

for M20A-FKS

Tester Connection

Condition

Result

A47-25 (IMO) - Body ground

Ignition switch turned to ON using registered door control transmitter assembly

Terminal IMO stuck low (2.4 V or less)

Terminal IMO stuck high (12 V) or abnormal waveform

Result

Proceed to

Terminal IMO stuck low (2.4 V or less)

A

Terminal IMO stuck high (12 V) or abnormal waveform

B
B

REPLACE ECM

for M20A-FKS: Click here 2020 MY Corolla Corolla Hatchback [01/2019 - 03/2019]; M20A-FKS (ENGINE CONTROL): ECM: REMOVAL 2020 - 2022 MY Corolla Corolla Hatchback [03/2019 - 09/2022]; M20A-FKS (ENGINE CONTROL): ECM: REMOVAL 2023 MY Corolla Corolla Hatchback [09/2022 - 11/2022]; M20A-FKS (ENGINE CONTROL): ECM: REMOVAL

for 2ZR-FAE: Click here 2020 MY Corolla [01/2019 - 03/2019]; 2ZR-FAE (ENGINE CONTROL): ECM: REMOVAL 2020 - 2022 MY Corolla [03/2019 - 09/2022]; 2ZR-FAE (ENGINE CONTROL): ECM: REMOVAL 2023 MY Corolla [09/2022 - 11/2022]; 2ZR-FAE (ENGINE CONTROL): ECM: REMOVAL

A

8.

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

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

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

Standard Resistance:

for 2ZR-FAE

Tester Connection

Condition

Specified Condition

I67-10 (EFII) - A46-45 (IMO)

Always

Below 1 Ω

I67-10 (EFII) or A46-45 (IMO) - Other terminals and body ground

Always

10 kΩ or higher

for M20A-FKS

Tester Connection

Condition

Specified Condition

I67-10 (EFII) - A47-25 (IMO)

Always

Below 1 Ω

I67-10 (EFII) or A47-25 (IMO) - Other terminals and body ground

Always

10 kΩ or higher
OK

REPLACE TRANSPONDER KEY ECU ASSEMBLY 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 03/2019]; THEFT DETERRENT / KEYLESS ENTRY: TRANSPONDER KEY ECU: REMOVAL 2020 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [03/2019 - 09/2022]; THEFT DETERRENT / KEYLESS ENTRY: TRANSPONDER KEY ECU: REMOVAL 2023 MY Corolla Corolla Hatchback Corolla HV GR Corolla [09/2022 - 11/2022]; THEFT DETERRENT / KEYLESS ENTRY: TRANSPONDER KEY ECU: REMOVAL

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

9.

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

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

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

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

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

Standard Resistance:

for 2ZR-FAE

Tester Connection

Condition

Specified Condition

I67-10 (EFII) - A46-45 (IMO)

Always

Below 1 Ω

I67-10 (EFII) or A46-45 (IMO) - Other terminals and body ground

Always

10 kΩ or higher

for M20A-FKS

Tester Connection

Condition

Specified Condition

I67-10 (EFII) - A47-25 (IMO)

Always

Below 1 Ω

I67-10 (EFII) or A47-25 (IMO) - Other terminals and body ground

Always

10 kΩ or higher
OK

REPLACE ECM

for M20A-FKS: Click here 2020 MY Corolla Corolla Hatchback [01/2019 - 03/2019]; M20A-FKS (ENGINE CONTROL): ECM: REMOVAL 2020 - 2022 MY Corolla Corolla Hatchback [03/2019 - 09/2022]; M20A-FKS (ENGINE CONTROL): ECM: REMOVAL 2023 MY Corolla Corolla Hatchback [09/2022 - 11/2022]; M20A-FKS (ENGINE CONTROL): ECM: REMOVAL

for 2ZR-FAE: Click here 2020 MY Corolla [01/2019 - 03/2019]; 2ZR-FAE (ENGINE CONTROL): ECM: REMOVAL 2020 - 2022 MY Corolla [03/2019 - 09/2022]; 2ZR-FAE (ENGINE CONTROL): ECM: REMOVAL 2023 MY Corolla [09/2022 - 11/2022]; 2ZR-FAE (ENGINE CONTROL): ECM: REMOVAL

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR