Toyota Tacoma 2015-2018 Service Manual: Additional Key cannot be Registered

Toyota Tacoma 2015-2018 Service Manual / Door Lock / Smart Key System(for Entry Function) / Additional Key cannot be Registered

DESCRIPTION

If additional registration is not possible, a malfunction in the certification ECU (smart key ECU assembly), engine switch, electrical key transmitter sub-assembly or steering lock ECU (steering lock actuator or UPR bracket assembly) is suspected.

CAUTION / NOTICE / HINT

NOTICE:

If registration of an electrical key transmitter sub-assembly is not possible, first confirm the procedure by engine immobiliser system. (See page ).
The smart key system (for Entry Function) uses a multiplex communication system (LIN communication system) and the CAN communication system. Inspect the communication function by following How to Proceed with Troubleshooting. Troubleshoot the smart key system (for Entry Function) after confirming that the communication systems are functioning properly (See page ).
When using the Techstream with the engine switch off, connect the Techstream to the DLC3 and turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the Techstream and the vehicle begins. Then select the vehicle type under manual mode and enter the following menus: Body Electrical / Smart Key. While using the Techstream, periodically turn a courtesy light switch on and off at intervals of 1.5 seconds or less to maintain communication between the Techstream and the vehicle.
Before replacing the certification ECU (smart key ECU assembly), steering lock ECU (steering lock actuator or UPR bracket assembly) and electrical key transmitter sub-assembly, refer to the smart key system (for Entry Function) (See page ).

HINT:

When additional registration is not possible, some freeze frame data may be stored in the certification ECU (smart key ECU assembly) (See page If freeze frame data is available, it can be helpful in determining whether any ).

If freeze frame data is available, it can be helpful in determining whether any parts were malfunctioning or not or narrowing down the suspected areas based on the table below.

Certification ECU Log of ID Code Registration

Parameter Name	Cause of Problem and Countermeasure
Failed Registration Mode	Make sure that another mode or a different registration mode is not selected, and then restart registration.
Key Registration Max	The registration was not possible because the maximum number of the electrical key transmitter sub-assemblies has already been registered to the certification ECU (smart key ECU assembly). If a new electrical key transmitter sub-assembly needs to be registered, such as when one of the registered electrical key transmitter sub-assemblies has been lost, erase an unnecessary ID code first. (See page ).
Key Verification: Amp Abnormal	Although a registered electrical key transmitter sub-assembly was held near the engine switch, electrical key transmitter sub-assembly registration could not be confirmed due to a malfunction of the immobiliser amplifier, such as a short to ground. DTC B278A or B2784 was stored.
Key Verification: Read Error	A registered electrical key transmitter sub-assembly was not held near the engine switch properly or electrical key transmitter sub-assembly registration cannot be confirmed due to wave interference, etc. Reregister the electrical key transmitter sub-assembly using the correct procedure or use another registered electrical key transmitter sub-assembly.
Transponder Key Amp Abnormal	Although an unregistered electrical key transmitter sub-assembly was held near the engine switch, electrical key transmitter sub-assembly registration cannot be completed due to a malfunction of the immobiliser amplifier, such as a short to ground. DTC B278A or B2784 was stored.
New Key Registration Error	An unregistered electrical key transmitter sub-assembly was not held near the engine switch properly or electrical key transmitter sub-assembly registration cannot be confirmed due to a malfunction, such as wave interference. Reregister the electrical key transmitter sub-assembly using the correct procedure or use another registered electrical key transmitter sub-assembly.
New Key Vehicle ID Error	Although the vehicle ID stored in the certification ECU (smart key ECU assembly) should be registered to the electrical key transmitter sub-assembly during electrical key transmitter sub-assembly registration, it was not successful. Use another unregistered electrical key transmitter sub-assembly for registration.
New Key Registration Failed	Although an unregistered electrical key transmitter sub-assembly was held near the engine switch for registration, electrical key transmitter sub-assembly registration was not successful due to wave interference (such as radio waves emitted from a device in the cabin) or a low transmitter battery.
New Key Already Registered	As a registered electrical key transmitter sub-assembly was held near the engine switch by mistake, electrical key transmitter sub-assembly registration was not successful. Using an unregistered electrical key transmitter sub-assembly, perform the registration procedure again.
New Key ID Code Error	Replace the certification ECU (smart key ECU assembly)
New Key Information Abnormal	The ID code of an electrical key transmitter sub-assembly could not be registered to the certification ECU (smart key ECU assembly). If 2 electrical key transmitter sub-assemblies are held near the engine switch at the same time, incorrect registration information will be stored in the certification ECU (smart key ECU assembly), suspending registration. Reregister the electrical key transmitter sub-assembly using the correct registration procedure.

PROCEDURE

1.	CHECK FOR DTC

(a) Check for DTCs.

NOTICE:

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

OK:

DTC is not output.

GO TO DIAGNOSTIC TROUBLE CODE CHART

2.	CHECK STEERING LOCK SYSTEM

(a) Check that the steering wheel unlocks.

OK:

The steering wheel unlocks.

HINT:

Check that the communication between the steering lock ECU (steering lock actuator or UPR bracket assembly) and certification ECU (smart key ECU assembly) is normal.

GO TO STEERING LOCK SYSTEM

3.	REGISTRATION

(a) Using other unregistered electrical key transmitter sub-assemblies, perform the additional registration procedure.

OK:

Additional registration can be completed.

REPLACE ELECTRICAL KEY TRANSMITTER SUB-ASSEMBLY

4.	REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

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

HINT:

For replacement, (See page ).
For registration, (See page ).

OK:

The key ID can be registered.

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

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