KeyDiy KD Universal 8A Smart Remote Key 4 Button For Lexus TB42-4

The KEYDIY TB42-4 is a universal smart key from KEYDIY's TB Series, purpose-built for Lexus vehicles equipped with the 8A smart key system. It features a 4-button layout and provides push-to-start / keyless-go functionality on compatible models.

Unlike KEYDIY's general-purpose B, NB, and ZB series, the TB Series is a specialized smart key designed specifically for the Toyota / Lexus 8A immobilizer architecture. It supports both fixed and dual frequency (315 MHz and 433 MHz), allowing a single TB remote to cover Toyota and Lexus models across multiple regions and frequency configurations.

Programming the TB42-4 requires a compatible KEYDIY tool — typically the KD-MAX or KD-X2 paired with the KD-MATE adapter, which is required for full Toyota / Lexus 8A smart key programming including all-keys-lost scenarios. KEYDIY's vehicle database is updated weekly to extend coverage to new Toyota and Lexus models as they're released.

As a smart proximity key, the TB42-4 includes the emergency insert blade — no separate blade purchase required.