Immobilizer System does not Operate Properly [12/2019 - 10/2021]: Procedure

1. Check for DTCs.

   Body Electrical > Smart Key > Trouble Codes 

   Powertrain > Engine > Trouble Codes 

   Result

   Result	Proceed to
   DTCs are not output	A
   DTCs are output	B

Result: 

B 

GO TO DIAGNOSTIC TROUBLE CODE CHART. Refer to  DIAGNOSTIC TROUBLE CODE CHART [12/2019 - 10/2021] 

Result: 

A 

See step  2

1. Read the Data List according to the display on the GTS.

   Powertrain > Engine > Data List 

   Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
   Immobilizer Fuel Cut Status	Status of immobilizer fuel cut	OFF or ON	-	-

   Powertrain > Engine > Data List 

   Tester Display
   Immobilizer Fuel Cut Status

   OK

   OFF is displayed after the engine is started.

   Result

   Proceed to
   OK
   NG

Result: 

OK 

GO TO SFI SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [12/2019 - 10/2022] 

Result: 

NG 

See step  3

1. Check that the engine starts 5 seconds after the ignition switch turned to ON.

   OK

   Engine starts normally.

   Result

   Proceed to
   OK
   NG

Result: 

OK 

USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [12/2019 - ] 

Result: 

NG 

See step  4

1. Disconnect the A19 certification ECU (smart key ECU assembly) connector.
2. Disconnect the A28 ECM connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   A19-3 (EFII) - A28-45 (IMO)	Always	Below 1 Ω
   A19-4 (EFIO) - A28-59 (IMI)	Always	Below 1 Ω
   A19-3 (EFII) or A28-45 (IMO) - Other terminals and body ground	Always	10 kΩ or higher
   A19-4 (EFIO) or A28-59 (IMI) - Other terminals and body ground	Always	10 kΩ or higher

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  5

1. Connect the A19 certification ECU (smart key ECU assembly) connector.
2. Connect the A28 ECM connector.
3. Using an oscilloscope, check the waveform.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Component with harness connected (Certification ECU (Smart Key ECU Assembly))	*b	Approximately 160 ms
   *c	Approximately 270 ms	*d	Approximately 40 ms
   *e	Approximately 60 ms	*f	Waveform (EFII)
   *g	Waveform (EFIO)	*h	Waveform A
   *i	Waveform B	*j	Waveform C
   *k	Waveform A (detail)	-	-

   NOTE:

   The waveform shown in the illustration is an example for reference only. Noise, chattering, etc. are not shown.

   OK

   Tester Connection	Condition	Tool Setting	Specified Condition
   A19-3 (EFII) - Body ground	Within 3 seconds of engine start or within 3 seconds of ignition switch turned to ON after auxiliary battery cable disconnected and reconnected	2 V/DIV., 500 ms./DIV.	Pulse generation (See waveform (EFII))
   A19-4 (EFIO) - Body ground	Within 3 seconds of engine start or within 3 seconds of ignition switch turned to ON after auxiliary battery cable disconnected and reconnected	2 V/DIV., 500 ms./DIV.	Pulse generation (See waveform (EFIO))

   Result

   Result	Proceed to
   Normal waveform	A
   Waveform A or C not output, or has abnormal wavelength or shape	B
   Waveform B not output, or has abnormal wavelength or shape	C

Result: 

B 

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [12/2019 - 11/2023] 

Result: 

C 

REPLACE ECM. Refer to  REMOVAL [12/2019 - 09/2020]  , or refer to  REMOVAL [09/2020 - 10/2022] 

Result: 

A 

See step  6

1. Register the ECU communication ID.

   HINT: 

   Refer to Registration.

   Refer to REGISTRATION [12/2019 - 10/2021]

   Result

   Proceed to
   NEXT

Result: 

NEXT 

See step  7

1. Check that the engine starts.

   OK

   Engine starts normally.

   Result

   Proceed to
   OK
   NG

Result: 

OK 

END (COMMUNICATION ID REGISTRATION WAS DEFECTIVE) 

Result: 

NG 

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [12/2019 - 11/2023]