Lexus Key Fob Replacement: FCC IDs, Board Numbers & Programming

A Lexus key fob replacement is matched by FCC ID plus the four-digit board number printed on the circuit board or the back of the case (0140, 3370, 5290, 6601, 0020, 0351 or 6100), because Lexus re-uses one FCC ID across several boards that will not program to each other. Most 2005–2012 Lexus smart keys are HYQ14AAB, HYQ14AEM or HYQ14ACX on a 4D chip; 2013 onward moves to HYQ14FBA and later HYQ14FBB, HYQ14FLC on the 8A chip; and older twist-ignition Lexus use a TOY48 remote head key with a 4D68 chip. Lexus uses the same Toyota smart-key boards, so tool support is broad, but all-keys-lost on 8A vehicles takes an extra step.

Which Lexus key generation is it?

Lexus is Toyota's premium line, and the immobilizer hardware follows Toyota's schedule almost exactly. The quickest tell is the start method plus the chip generation, and the board number narrows it from there. Years overlap at every transition, so verify on the vehicle.

Two identification habits save a lot of returns. First, flip the customer's fob and read the board number before you read the FCC ID; a 2011 ES350 and a 2011 RX350 both say HYQ14A-something on the label but need different boards. Second, on the 4D-era smart keys note whether the fourth button is trunk or hatch: the ES sedan and the RX crossover use different button assignments even where the board matches.

Lexus FCC IDs and boards locksmiths look up most

HYQ14FBA is the one to be careful with. The same FCC ID carries a G board (0020) for the ES and GS sedans and an AG board for the IS and RC, and the Toyota version of the same ID uses yet another board for the Highlander. The FCC ID gets you to the shelf; the board gets you to the right box. Our companion article on the Toyota HYQ14 smart key family covers the board list across both brands.

Lonsdor LT20 boards for Lexus: when a universal board is the better buy

Lonsdor's LT20 series is a set of smart-key circuit boards with adjustable frequency that drop into Toyota and Lexus shells, generated with the Lonsdor K518 family or the KW100 Bluetooth programmer. For a shop that sees a lot of Lexus, they solve the board-number problem differently: instead of stocking six vehicle-specific fobs, you stock two or three LT20 boards and a few shells.

• LT20-03 — 4D chip, 4-button, for 2006–2015 Toyota and Subaru boards; use it where a Lexus needs a 4D-era board and you have a good shell.
• LT20-07 — 8A chip, 4-button, for Lexus 2017–2020 in the HYQ14FBF shell.
• LT20-10-4 — 8A + BA chip, 4-button, for 2020–2024 Toyota and Lexus in the HYQ14FBX shell.
• LT20-10-6 — 8A + BA chip, 6-button, for the 2020–2024 Toyota and Lexus vehicles that use the six-button layout.

The KW100 handles both add-a-key and all-keys-lost generation for LT20 boards and pairs by Bluetooth to the Lonsdor app, so a mobile tech can generate the board on the driveway. The trade-off is that LT20 boards are Lonsdor-ecosystem parts: if your primary tool is Autel or Xhorse, a vehicle-specific aftermarket fob is the simpler purchase. The Lonsdor universal smart keys guide goes board by board.

How Lexus smart keys are programmed

• Add-a-key with one working smart key (any generation). OBD on Autel IM508/IM608, Xhorse VVDI Key Tool Plus, Lonsdor K518 and similar. Place the new fob on the start button when prompted. Routine on 4D and 8A vehicles alike.
• All-keys-lost, 4D era (2005–2012). The tool resets the smart ECU (often called a "smart box reset" or immobilizer reset in the menus) and then registers the new fob. Some tools need the vehicle to sit through a timed wait; budget for it.
• All-keys-lost, 8A era (2013 onward). The 8A system will not accept a new key by OBD alone without a working key present. The standard route is an emulator or simulator key that the tool generates from the vehicle's data, used in place of the missing key, after which the real fob is added normally. Autel, Lonsdor and Xhorse all offer this for Toyota/Lexus 8A; check that your tool lists the specific Lexus model year, and expect a longer job than an add-a-key.
• Remote head keys (HYQ1512V, HYQ12BBT). Transponder by OBD tool; remote functions by the Toyota onboard door-lock procedure on many models, or by tool where the onboard sequence is not supported. Verify on the vehicle.

Lexus vehicles read the fob at 315 MHz in North America. A fob with the correct board but wrong regional frequency will pass programming and then fail at range; buy the North American version.

Entry, blades and shells

Twist-ignition Lexus and the emergency blade in every Lexus smart key use the TOY48 high-security keyway. The Original Lishi TOY48 2-in-1 reads the ignition, door and trunk, which makes it the one Lishi tool a Lexus-heavy shop should not be without; the broader set is in the Lishi tools hub. Xhorse also makes a Lexus-style 3-button universal flip key (XELEX0EN, XT27 super chip) for VVDI users who want a flip-key option on older TOY48 vehicles.

What Car Key Source stocks for Lexus

All Lexus-specific fobs in the catalog are aftermarket; the genuine OEM range for Toyota-family vehicles is on the OEM hub.

The make page is at Lexus keys and remotes, with the Toyota side at Toyota key fob replacement. Trade pricing is unlocked with an approved wholesale account — most applications are approved instantly; apply here. In-stock orders placed by 4 PM ET (Mon–Fri) leave the warehouse the same business day. If a key or remote won't program on the vehicle we listed it against, it is refunded within 30 days of delivery and we pay the return freight.

FAQ

Will a Toyota HYQ14FBA fob program to a Lexus?

Only if the board number matches. HYQ14FBA is shared across Toyota and Lexus, but the ES/GS use the G board 0020, the IS/RC use the AG board, and the Toyota Highlander uses the 2110 board. A matching FCC ID with the wrong board will fail at programming or program and then not start the car.

Can I do a Lexus all-keys-lost without the dealer?

Yes on both the 4D and 8A generations. The 4D-era smart keys (2005–2012) take a smart ECU reset followed by a normal registration. The 8A era (2013 onward) needs an emulator key generated by the tool before the real fob is added; Autel, Lonsdor and Xhorse support it, though coverage by model year varies, so confirm before quoting.

What is the board number and where is it?

It is a four-digit code (0140, 3370, 5290, 6601, 0020, 0351, 6100) printed on the circuit board and usually on the label on the back of the fob, next to the FCC ID. It identifies the transponder and radio configuration, which the FCC ID alone does not.

Which Lishi tool opens a Lexus?

The Original Lishi TOY48 covers the ignition, door and trunk on Toyota and Lexus high-security locks, including the emergency blade cylinder on smart-key vehicles.

Are Lonsdor LT20 boards a substitute for vehicle-specific Lexus fobs?

For a Lonsdor-equipped shop, yes for most 2006–2024 smart-key Lexus models, because the boards are generated to the vehicle and dropped into a matching shell. If your main programmer is a different brand, a vehicle-specific aftermarket fob is the more straightforward buy.