2023 Lexus IS300 all smart keys lost is done by Autel MaxiIM KM100. The device makes the lost key by itself. It does not need to backup immo data or need a 12-digit outcode.
Procedure:
Connect VCI with OBD, pair KM100 with VCI200 via bluetooth.
Select IMMO->Lexus->Manual Selection->USA->IS300->2016-2020->Smart Key->Control Unit-> Keyless System (CAN)
Read number of keys. 2 keys were programmed.
Failed to backup immo data on this model.
So we do a smart box reset.
Smart box reset succeed.
Add smart key
Learn key succeeded.
If remote control is not working, follow instruction here to enable remote keyless function.
Autel MaxiIM KM100 does have the ECU Synchronization Learning Function Follow this function route on the KM100 IMMO – Lexus – System Selection – Keyless System – Keyless System (CAN) – ECU Synchronization Learning