2021 Subaru WRX Key Replacement

2021 WRX key specs

From 2015 the WRX and STI became their own model, and most cars use a four-button remote-head key with a side-cut blade. Upper trims added Keyless Access with push-button start, using a smart fob with an emergency blade inside. Subaru's bulletin shows the 2015 smart key with a different emergency key from 2016 and later cars, and the 2020 remote-head key has a new part number, so check the part number on your old key.

What's specific to the 2021 WRX

2021 was the final model year of the WRX VA (first standalone generation), before the VB (second standalone generation) arrived for 2022. Late-run cars occasionally pick up running changes, so we check the VIN instead of assuming a 2021 Subaru WRX matches a 2015.

A 2021 Subaru WRX is about 5 years old now. Original fob batteries are near the end of their life at this age, so weak range or a "key not detected" message is often a battery before it is a failed fob. Cars this age are often on their second owner, which is when a single remaining key and a request for a spare tend to show up.

Key options for the 2021 Subaru WRX

• Remote head key. A remote-head key puts two separate systems in one piece: a cut blade with a transponder chip that the immobilizer reads, and a small circuit board with buttons that signals the body control module to work the door locks. On a 2021 Subaru WRX with this style of key, each side is programmed separately. That explains some confusing failures. If the remote stops working but the car still starts, the problem is usually the battery or the remote board. If the buttons work but the engine won't run, look at the chip side. Knowing which half failed tells us whether you need a repair, a reprogram or a whole new key.
• Smart proximity key (push-to-start). Making a new smart key is mostly a programming job. The fob has to match the vehicle's FCC ID, frequency and chip, and then the keyless system must be told to accept it, normally through the OBD-II port. Depending on the platform, that can mean entering a PIN, waiting through a timed security procedure, or on some newer vehicles, using manufacturer online access. When every key is lost, certain models need a module removed and read on the bench. For your Subaru WRX VA (first standalone generation), we'll tell you which of those applies, and if a step is dealer-only, you'll hear it before we drive out. The emergency blade hidden inside the fob is cut by code during the same visit.

How the Subaru immobilizer works on the WRX

• Subaru's bulletin lists the 2015 WRX and STI smart key with a 5+4 laser emergency key and a thinner 4+4 key from 2016.
• The 2015-2019 WRX remote-head key, FCC ID CWTWB1U811, is the same part used on several Imprezas and Foresters of the era.
• The STI used the same keys as the WRX of its year and ended US sales after 2021.

Programming a 2021 WRX key

With a working key, adding a remote-head key or Keyless Access fob is routine through the OBD-II port, and the remote is registered in the same pass. Smart fobs must be new or reset to blank. When every key is lost, remote-head cars are handled with Subaru's immobilizer data, while smart-key cars can need special tools or the dealer. 2020-2021 cars carry a new key part number, so we confirm the chip before ordering.

Spare keys are routine. All-keys-lost on remote-head cars is usually fine, but Keyless Access cars can need special tools or the dealer.

Lost every key to your WRX?

With every key gone, the model year decides the job. A 2000-2004 Subaru, a Baja, or a base model built before its line got an immobilizer just needs a key cut by code or by decoding the door lock. On 4D62 cars from 2005 through 2011 and on remote-head cars of the G-chip years, we cut the blade, erase the missing keys and program new ones in one visit. Keyless Access cars of the G-chip years and every H-chip car are harder: some tools need a working key, so we use dedicated Subaru software or an emulator, and a few cars have to go to the dealer. Brand-new platforms, including the 2026 Outback and Subaru's electric models, are usually dealer jobs for now. We tell you plainly which route your car needs and check ID and proof of ownership before any work.

1. Gather your documents and the VIN. Call with the year, make, model and VIN if you can read it through the windshield, plus where the car is parked. Those details let us confirm whether your Subaru WRX can be done on-site and bring the right key, so the first trip is the only trip.
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. All-keys-lost programming often takes longer than adding a key, because the car has no trusted key to authorize the change. We follow the procedure your Subaru WRX requires, then confirm the engine starts and keeps running and the remote or keyless functions respond.
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.

Why a spare key pays for itself

• Some vehicles make it hard to add a key once you're down to one. Certain immobilizer systems let an owner program an extra key on-board only when two working keys are present, so a second key preserves the easy options for later and avoids a full reset.
• Electronics fail without warning. A fob dropped on concrete, run through the washing machine or soaked at the pool can quit for good. With a second programmed key, that's an annoyance you fix on your own schedule, not a stranded car that needs attention today.
• When you sell or trade in the vehicle, buyers and dealers expect two keys. A missing key can come up during an appraisal or a private-sale negotiation, so having both on hand keeps the conversation about the car, not about what it will cost the next owner to replace one.

Dealer or mobile locksmith?

Price and parts are the other half of the comparison. Dealers typically sell factory keys only and charge their posted service rates for programming. We offer factory keys where it matters and quality aftermarket alternatives where they perform well, and the quote covers cutting, programming and the trip, with nothing tacked on at the end. Timing differs too. Dealer service departments generally keep business hours, while we take automotive calls every day from 6:30 a.m. to 11:30 p.m., which covers early commutes and late evenings. We're closed overnight, and we'll be upfront if your timing means the dealer or a next-day visit is the better plan. Neither option is wrong; the right one depends on your WRX and your schedule.

WRX key battery

Battery details for the 2021 WRX: CR1620 (remote-head key); CR2032 (most smart fobs). Swap cells one at a time and match each one exactly; if a key still fails with a fresh battery, the board, buttons or programming may be the problem, which we can test on site.

How the job works

1. Identify the exact key your WRX 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. A key is cut from a code, not a guess. When the factory code can be retrieved through manufacturer channels after ownership is verified, we use it. When it can't, we decode a door lock with a pick-decoder tool that reads the wafer positions without damaging anything, then work out any missing cuts.
4. Cut the blade on-site. Cutting happens right beside your car. For a smart key, that means the emergency blade hidden inside the fob; for a transponder or remote-head key, it's the main blade you'll use every day. We deburr the cuts and check the fit in each lock so nothing binds or sticks later on.
5. Program the chip, remote or smart key. Programming tells the car's computers that the new key belongs to the vehicle. Transponder chips are added to the immobilizer, remote buttons to the body control module, and proximity fobs to the keyless system. If a step requires dealer-only access on your WRX, you'll have heard that before we arrived, not halfway through the job.
6. Test everything and clear out old keys. The last step is a short walkthrough. We show you how many keys the car now recognizes, point out the dead-fob start method for your vehicle, and hand you an itemized receipt. If a spare makes sense, it's simplest to add it during this same visit while the equipment is already connected.

What affects the price of a WRX 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 Subaru WRX is the most involved of all, both in the part itself and in the programming.
• All keys lost or adding a key. Adding a key while a working one is in hand is the simpler job. With every key gone, we may have to open the car, decode a lock to originate the cuts, and run a longer programming routine, so all-keys-lost work takes more time and costs more.
• 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 Subaru system adds equipment time and labor to the job.
• Travel, timing and extra repairs. Sometimes a key problem is really a lock problem: an ignition that won't turn even with the right key, or a door cylinder that has been jammed for years. Fixing those is separate work. We point them out, explain the options, and quote the whole job up front so the bill holds no surprises.

Call (951) 903-3193 with your VIN and the keys you still have, and we'll quote the job before any work starts.

Common Subaru key problems

• Subaru remotes of one era were built on two frequencies under different FCC IDs: CWTWB1U811 at 315 MHz and CWTWBU766 at 433.92 MHz. Both appear on remote-head keys for 2010-2015 Subarus, so match the part number printed on your old key before you buy a replacement.
• Used Subaru fobs sold online can arrive already programmed to another car. Ask whether a fob is new or reset to a blank state before you buy, and bring the part number and FCC ID from your old key so we can confirm the fit before programming.
• Remote-head key shells tend to crack at the blade root after years on a heavy keyring. The remote board and transponder can usually be moved into a new shell with a freshly cut blade, which often costs less than a complete new key.
• Remote-head keys from 2012 through at least 2022 mostly run on a CR1620 cell, while Keyless Access fobs from 2014 on take a CR2032. The 2024 remote-head key moved to a thicker CR2025. Inland Empire summer heat shortens coin-cell life, and shrinking range is the usual warning.

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.
• Learn your car's dead-fob start method now, in the driveway, rather than in a dark parking lot later. Depending on the make, you hold the fob against the start button or place it in a marked pocket in the console. Also find the hidden keyhole on the driver's door handle and practice using the emergency blade.
• Make the spare before you need it. Adding a key while one still works is quicker and less expensive than starting from nothing, and it keeps the simpler programming options available. Good moments are right after buying the car, or as soon as one of your two keys goes missing.

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.

Need a 2021 Subaru WRX key?

Need a key for your 2021 Subaru WRX? Call Julian's Locksmith at (951) 903-3193 with your VIN and tell us which keys you still have. We'll confirm what the job involves, give you a quote before any work starts, and come to you in Southern California with everything needed to cut and program the key on the spot.