Additional Key cannot be Registered [12/2019 - 10/2021]: Procedure

1. Check for DTCs.

   Body Electrical > Smart Key > Trouble Codes 

   NOTE:

   If a malfunction occurs, do not remove/install the vehicle auxiliary battery before checking for DTCs.

   OK

   DTCs are not output.

   Result

   Proceed to
   OK
   NG

Result: 

NG 

GO TO DIAGNOSTIC TROUBLE CODE CHART. Refer to  DIAGNOSTIC TROUBLE CODE CHART [12/2019 - 11/2023] 

Result: 

OK 

See step  2

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

   Body Electrical > Smart Key > Data List 

   Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
   Unmatched Vehicle-ID	Key No. (incorrect or correct)	No or Yes	No: Communication normal Yes: Communication malfunction	The vehicle ID registered in the vehicle and the vehicle ID registered in the electrical key transmitter sub-assembly are different (if a key from another vehicle is brought into the vehicle exterior detection area while the doors are locked, "Yes" is displayed for "Unmatched Vehicle-ID" in the Data List). Other potential causes: An electrical key transmitter sub-assembly from a different vehicle is being used. A communication error due to wave interference. The electrical key transmitter sub-assembly or certification ECU (smart key ECU assembly) is malfunctioning.

   Body Electrical > Smart Key > Data List 

   Tester Display
   Unmatched Vehicle-ID

   Result

   Result	Proceed to
   "No" is displayed	A
   "Yes" is displayed	B

Result: 

B 

See step  5

Result: 

A 

See step  3

1. Remove the transmitter battery from the electrical key transmitter sub-assembly.
2. With the brake pedal depressed, hold the electrical key transmitter sub-assembly near the engine switch and check if the power source mode changes.

   OK

   The power source mode changes.

   HINT: 

   If the power source mode changes, the cabin verification is malfunctioning.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *1	Engine Switch
   *2	Electrical Key Transmitter Sub-assembly

   Result

   Result	Proceed to
   The power source mode changes	A
   The power source mode does not change	B

Result: 

B 

GO TO SMART KEY SYSTEM (for Start Function) (Power Source Mode does not Change to ON (IG and ACC)). Refer to  Power Source Mode does not Change to ON (IG and ACC) [12/2019 - 10/2022] 

Result: 

A 

See step  4

1. The ignition switch is ACC or ON.
2. Check that the steering unlocks.

   HINT: 

   • When the ignition switch is turned to ACC or ON and the electrical key transmitter assembly and certification ECU (smart key ECU assembly) are verified, the steering is unlocked.
   • Check that the communication between the steering lock ECU (steering lock actuator or upper bracket assembly) and certification ECU (smart key ECU assembly) is normal.

   OK

   The steering unlocks.

   Result

   Proceed to
   OK
   NG

Result: 

NG 

GO TO SMART KEY SYSTEM (for Start Function) (Unable to Unlock Steering Wheel (Engine cannot Start)). Refer to  Unable to Unlock Steering Wheel (Engine cannot Start) [12/2019 - 10/2021]  

Result: 

OK 

See step  5

1. Using an unregistered electrical key transmitter sub-assembly, perform the additional registration procedure.

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

   OK

   Additional registration can be completed.

   Result

   Proceed to
   OK
   NG

Result: 

OK 

REPLACE ELECTRICAL KEY TRANSMITTER SUB-ASSEMBLY (FIRST REGISTERED KEY WAS DEFECTIVE) 

Result: 

NG 

See step  6

1. Temporarily replace the certification ECU (smart key ECU assembly) with a new one and register the electrical key transmitter sub-assemblies.

   HINT: 

   • For replacement.

     Refer to REMOVAL [12/2019 - 11/2023]

   • For registration.

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

   OK

   All of the electrical key transmitter sub-assemblies could be registered to the new certification ECU (smart key ECU assembly) successfully.

   Result

   Proceed to
   OK
   NG

Result: 

OK 

END (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) WAS DEFECTIVE) 

Result: 

NG 

GO TO OTHER PROBLEM (New key cannot be Registered). Refer to  New Key cannot be Registered [12/2019 - 10/2021]