The 2001–2005 IS uses the same key setup, so everything on this page applies to those years too. The full picture is on the Lexus IS key guide.

2005 Lexus IS: key facts

Key type: Transponder chip key
Push-to-start: No
Transponder chip: 4C
Programming: OBD
All keys lost: We can originate new keys on site

IS300: 4C chip on the short laser-cut TOY48 blade. All-keys-lost on the earliest cars can require an immobilizer ECU reset rather than a quick OBD add — confirmed by year and VIN.

Same key system as the 2001–2005 IS

Lexus kept the IS's key system unchanged across 2001–2005, so everything about replacing a 2005 key — blanks, programming, and what happens if every key is lost — matches the rest of that run. The full year-by-year breakdown lives in our Lexus IS key guide.

What drives the price is the key type, whether you still have a working key, and where the car is parked. There's more on Lexus programming in general on our Lexus key page.

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Reviewed by David, Owner & Lead Technician, Wilshire Lock & Key — in the locksmith trade since 1987.

Last updated 2026-10-11.

2005 Lexus IS key replacement

2005 Lexus IS: key facts

Same key system as the 2001–2005 IS

We cover all these cities