Acura NSX Key Replacement

NSX keys by generation

The hybrid NSX starts with a push button and uses a smart key that stays in your pocket. Parts catalogs list a four-button fob for 2017-2022 cars carrying FCC ID KR5V2X, the same ID used on the 2018-2020 TLX, but the car was built in small numbers at Acura's Performance Manufacturing Center in Ohio and we have not confirmed which fobs and programming routes work on it. Like other Acura smart keys, the fob contains a mechanical emergency key for the driver's door, which matters if the fob battery runs down while the car sits. Programming a second-generation NSX key is normally done by an Acura dealer with Honda's diagnostic equipment, because we have not confirmed aftermarket programmer coverage for this hybrid and a fob that is cut and registered incorrectly can cost you a second visit. What we can do is open the car if you're locked out, cut the emergency blade, and help you line up the dealer appointment with the right ownership paperwork.

The 2000-2005 NSX uses a conventional chip key with a Megamos 13 transponder in its head, sharing its blade and chip family with the TL, CL and RL of the period. That keeps blanks available even though the car itself is rare. Many of these cars have spent long stretches in storage, so a worn or brittle original key is common, and cutting a new key to the code gives a cleaner result than copying the old one. A spare for a fixed-code Megamos 13 key can often be cloned from a working original without connecting to the car. Originating a key with none left means programming the immobilizer through the diagnostic port, and on a low-volume car like the NSX we confirm that our programmer supports your exact year before starting. If it doesn't, we can cut the key and coordinate programming with an Acura dealer.

Acura key security

Acura fitted an immobilizer to essentially every car it sold here from 2000 on, and the type of chip tells you a lot about how a replacement key gets made. Through the early 2000s, the TL, CL, RL, MDX, RSX, NSX and 2000-2001 Integra used a Megamos 13 fixed-code transponder inside a conventional key, with keyless entry handled by a separate remote. The 2004 TL and TSX introduced Philips ID46 (Hitag 2) crypto chips, which later moved into flip keys on the MDX, RDX, TL and TSX. The 2005 RL brought Acura's Keyless Access smart key, and by the late 2010s nearly every Acura used push-button start with a Philips ID47 (Hitag 3) smart fob. The newest designs, such as the 2022-and-later MDX and RDX, the 2023 Integra and the ADX, use Honda's latest smart key generation, while the electric 2024 ZDX uses a GM-designed system. In every case the engine computer checks the chip before it lets the engine run, so a key that is only cut will turn the ignition without starting the car. A flashing key symbol on the dash usually means the car didn't recognize the chip.

Most Acura key programming happens through the OBD-II port under the dash with a professional key programmer. There's no owner-side procedure for the immobilizer chip, although the separate keyless entry remotes used from about 2000 to 2008 can usually be paired on board with Honda's timed ignition-and-lock-button routine. Flip keys and smart keys get their remote functions registered along with the chip. Two habits save trouble. First, bring every key you still use, because Honda's registration routine can drop keys that aren't present. Second, check the FCC ID and part number on your current fob, since Acura fobs run on several frequencies (308, 312, 314, 315 and 434 MHz) and many come in Driver 1 and Driver 2 versions tied to seat memory. Laser-cut blades are cut to code on a dedicated machine. We verify your ID and proof of ownership before any key is made.

All NSX keys lost

Losing every key to an Acura is usually fixable where the car sits, but the path depends on the year. For cars with Megamos 13 or ID46 chips, roughly 2000 to 2013 including the flip-key models, we cut a key to your locks by code or by decoding a lock, then program it to the immobilizer through the OBD-II port. Most push-button models from about 2009 to 2020 follow the same pattern with a new smart fob, though low-volume cars like the RL, RLX and first ZDX can take extra steps. The newest platforms, such as the 2022-and-later MDX and RDX, the current Integra, the ADX and the 2021-2025 TLX, depend on current tool coverage, while the hybrid NSX and electric ZDX are dealer jobs. Before anything is cut, we check your photo ID against the registration or title.

1. Gather your documents and the VIN. Find your registration or title and a government photo ID in the same name. Note the VIN, which is printed on the driver's side of the dashboard and usually on your insurance card. If the paperwork is locked in the car, tell us; we'll open the vehicle first and check it there.
2. Get into the vehicle without damage. If the car is locked, we open it with non-destructive tools such as an inflatable wedge and a long-reach rod, or by picking the door lock. Some vehicles need a careful approach to avoid triggering the alarm, which can interfere with programming later.
3. Originate a new key from the car. With no key to copy, the cuts come from the vehicle itself. We retrieve the key code through manufacturer channels where possible, or decode a door lock with a pick-decoder tool. Then we cut the blade on our code machine and confirm it turns the lock smoothly.
4. Program the key to the immobilizer. Next, the new key is introduced to the car's security system. Many vehicles allow this through the OBD-II port with a PIN or security procedure. Some all-keys-lost cases require reading a module on the bench, and a few platforms only allow dealer programming, which we'll tell you up front.
5. Erase missing keys and add a spare. A lost key's metal blade can still open your doors even after its chip is erased. If the keys disappeared along with something showing where you live or park, consider rekeying the car's door lock cylinders too. We'll also recommend leaving with two working keys, not one.

Dealer or mobile locksmith?

The biggest difference between a dealership and a mobile locksmith is where the work happens. A dealer programs keys in its service bay, so if every key is lost, the car usually has to be towed there, and you work around the service department's schedule and the time it takes to order a key by VIN. Julian's Locksmith brings the cutting machine, key blanks and programming equipment to the car, whether it sits in your driveway, a workplace lot or a parking structure. For a 2022 Acura NSX we can program on-site, that means no tow and no shuttle rides back and forth. The trade-off is real, though: on vehicles where only the dealer can program keys, a tow or appointment may still be necessary, and we'll say so before you spend anything on our visit.

How the job works

1. Identify the exact key your NSX uses. We ask a few quick questions on the phone: the year, whether the car starts with a turn key or a button, how many keys you have left, and whether the remote still works the doors. Then we check the VIN against our programming references so the van arrives with the correct blank or fob, not a close guess.
2. Verify ownership before any work. Before cutting or programming, we compare your government photo ID with the vehicle registration or title and check that the VIN on the paperwork matches the VIN on the dash. If the registration is locked inside, we open the car first, confirm the documents, and only then make the key.
3. Get the key code or decode the lock. If you still have a working key, we can read its cuts directly and check them against the factory depths for the Acura keyway. A worn key gets corrected back to spec during this step, so the new key turns crisply instead of reproducing years of wear in a fresh piece of metal.
4. Cut the blade on-site. Our van carries a code-cutting machine that handles both traditional edge-cut blades and the laser-cut, side-milled profiles common on newer keys. The blade is cut to the code, then test-fitted in a door lock and the ignition or emergency keyhole to confirm smooth operation before any programming begins.
5. Program the chip, remote or smart key. With the blade done, we connect to the OBD-II port and register the new key with the immobilizer. Depending on the Acura system, this may involve a security PIN, a timed waiting period, or on-board button sequences for the remote. On some vehicles we clone a working key's chip instead, when that's the more reliable path.
6. Test everything and clear out old keys. Before we leave, every function gets checked: doors, trunk or liftgate, panic button, remote range, engine start, and the emergency blade in the driver's door. If keys are missing, we delete them from the car's memory where the system allows, so a lost key can no longer start the engine.

What affects the price of an NSX key

• The type of key. The biggest factor is technology. A plain mechanical key is a cutting job only. A transponder key adds a chip and programming. Remote-head and flip keys add a circuit board, and a proximity fob for a push-button Acura NSX is the most involved of all, both in the part itself and in the programming.
• Factory or aftermarket parts. Some owners want an exact factory match; others just want a dependable key that starts the car. Both are reasonable choices. The part you pick changes the quote, so we lay out the options side by side, with the trade-offs in fit, button feel and long-term durability, before you decide.
• All keys lost or adding a key. On some vehicles, losing the last key changes the programming entirely, from a quick add-key procedure to a full immobilizer reset or a module read on the bench. That extra labor shows up in the price, and it's the strongest argument for keeping a spare in the house.
• Programming complexity and security access. Some immobilizers accept a new key with a few on-board steps. Others need a PIN code, a timed security wait, manufacturer online access, or removing a module to read its data. Every extra layer of security on the Acura system adds equipment time and labor to the job.

NSX key types explained

• Transponder (chip) key. There are two ways to give a new transponder key the right identity. Cloning reads the chip in a working key and writes that same ID onto a special cloneable chip, so the car can't tell the two apart. Programming adds a brand-new key ID to the immobilizer's memory through the OBD-II port, sometimes after entering a security PIN tied to the VIN. Cloning is handy when you have a working key and the chip family supports it. Programming is the better choice when keys are lost, because it also lets us remove keys you no longer control from the car's memory. For your Acura NSX, we'll explain which method fits and why.
• Smart proximity key (push-to-start). A smart or proximity key lets a 2022 Acura NSX open when you touch the door handle and start with a push of a button while the fob stays in your pocket or bag. Antennas in the doors and cabin send out a low-frequency wake-up signal; the fob answers on a higher radio frequency with an encrypted reply, and the car only allows a start once it confirms the fob is inside. When the fob battery is weak, that conversation fails, which is why most designs include a backup: hold the fob against the start button or set it in a designated pocket. The owner's manual shows where, and it's worth checking before you need it.

Why a spare key pays for itself

• Two drivers sharing one key is a daily negotiation. A second key lets a partner, teenager or coworker use the vehicle without handing keys back and forth in parking lots, and it means one person losing their key ring doesn't leave the whole household stuck.
• A spare stored safely at home rescues you from a locked car with the fob sitting on the seat, a key dropped somewhere along a hiking trail, or a fob that stops responding on a busy morning. Keep it indoors, never in a magnetic box under the bumper.
• A spare turns a future all-keys-lost emergency into a simple add-a-key job. With one working key in hand, programming is quicker, and the chip or fob can often be paired without decoding locks or reading modules, which keeps the cost of a lost key far lower.

Tips from a mobile locksmith

• Photograph the back of your fob and any key tag that came with the car. The FCC ID, part number and key code printed there make ordering a replacement faster and more accurate. Store the photos somewhere you can reach from any device, not only on the phone that might go missing along with the keys.
• On any vehicle with a turn-key ignition, keep the key ring light. A heavy cluster of keys, tools and charms swings with every bump and slowly wears the ignition wafers and the key itself. When the key starts to stick or needs a wiggle to turn, deal with it early, before it stops turning entirely.
• When a key's head cracks or its blade bends, replace it before it fails. A transponder chip can slip out of a split head, and a bent blade can break off inside the ignition or door lock, turning a simple key replacement into an extraction and repair job. Small symptoms are the inexpensive time to act.
• Never hide a spare key or fob on the outside of the car. Magnetic boxes in wheel wells and under bumpers are the first places a thief checks, and with a proximity fob, a hidden key can let anyone open the doors and drive away. Keep the spare at home or with someone you trust.

Common Acura key problems

• Broken flip-key hinges on 2007-2013 MDX and RDX keys and 2009-2014 TL and TSX keys. The blade stops locking open or flops loose. A new shell can often reuse the original board and chip, but a cracked board means a new programmed key.
• Lost remotes on models with separate fobs. On the early TL, CL, RL, MDX, RSX and first-generation TSX, the chip lives in the key, so a missing remote only affects keyless entry and can be replaced on its own.
• Worn edge-cut keys on early-2000s Acuras. Two decades of use rounds off the cuts and makes the ignition sticky or hard to turn. A key cut to the factory code usually works better than a copy of the worn original.
• Weak smart key batteries. Most Acura smart fobs from 2009 on take a CR2032 coin cell. With a dying battery, holding the fob against the ENGINE START/STOP button usually lets the car read its chip and start anyway.
• Seized driver's door lock cylinders on smart key cars. The emergency blade almost never gets used, so the cylinder can corrode and refuse to turn the day the fob dies. Try your blade in the door lock every few months.
• Ordering the wrong fob online. Acura fobs that look identical can differ in frequency, transponder and memory position (Driver 1 or Driver 2). Match the FCC ID and part number on your current fob before buying, or let us source the part.
• Four-button spares on remote-start cars. Some 2014 and later Acuras shipped with a five-button fob that includes remote engine start. A four-button replacement will drive the car but won't start it remotely, so count your buttons before ordering.
• No-start after a key is dropped or run through the wash. A damaged chip can leave the key turning the ignition, or the fob locking doors, while the engine refuses to start. Testing the transponder tells us whether the key needs replacing.

Proof of ownership

Making car keys is regulated work in California. Locksmiths are licensed and overseen by the Bureau of Security and Investigative Services under the Locksmith Act, Business and Professions Code section 6980 and following, and Julian's Locksmith holds company license LCO7891. Verification protects you more than anyone: a locksmith who will make a key for whoever asks will also make one for someone who wants your car. We record your name, the vehicle and its VIN on a work order, and we politely decline jobs where ownership can't be established. You can look up our license at search.dca.ca.gov.