2004 Subaru Impreza Key Replacement

2004 Impreza key specs

Most second-generation Imprezas, including the 2.5i, 2.5RS, TS wagon and Outback Sport, use a plain cut key with no chip. Turbocharged models are the exception: the STi got an immobilizer and a 4D62 transponder key starting in 2005, and the WRX followed for 2006 and 2007. A 2002-2005 WRX and the 2004 STi still have plain keys. Keyless entry came as a separate fob in every case, with a two-button design common on 2005-2007 cars, so expect two pieces on your keyring.

What's specific to the 2004 Impreza

The 2004 Subaru Impreza is the third of 6 model years in the Impreza GD/GG (second generation) (2002–2007), so it shares its key system with the rest of that run, which makes replacement parts easy to source. A 2004 Subaru Impreza is about 22 years old. Original keys are often worn smooth, and some factory remotes for cars this age are discontinued, so we may suggest a quality aftermarket remote or a separate fob. Because older immobilizers are simpler, all-keys-lost jobs on cars this age are usually more straightforward than on late models.

If a newly cut key turns the 2004 Impreza's ignition but the engine cranks and dies, the transponder isn't recognized yet; that's a programming step, not a cutting problem, and it's handled at the car.

Key options for the 2004 Subaru Impreza

• Basic mechanical key. A plain mechanical key has no chip and no electronics, just a cut blade that lines up the wafers inside the lock. If your 2004 Subaru Impreza uses one, replacement is mostly a cutting job, but how it's cut matters. Copying a worn key copies its wear, and a duplicate of a duplicate drifts further from spec each time. We prefer to cut by code: we look up or decode the factory bitting, then cut a fresh key to the original depths on a code machine. The result turns smoothly in the doors and ignition instead of needing a jiggle. If the ignition wafers themselves are already worn, we'll point that out too.
• 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 Subaru Impreza, we'll explain which method fits and why.
• Key with separate remote fob. Some Subaru Impreza owners carry two pieces: a transponder key for the ignition and a separate remote fob on the same ring. Because they work independently, you only have to replace what's actually missing or broken. A lost remote still leaves you with a key that opens the doors and starts the engine, so it's an inconvenience rather than an emergency. A lost key is the more urgent half, since it has to be cut and its chip programmed before the car will run. We stock and program both sides, and if the whole ring is gone, we handle the key first and then pair a new remote.

How the Subaru immobilizer works on the Impreza

Subaru came to engine immobilizers later than most brands sold in the US, which keeps things simple for owners of early-2000s models: no 2000-2004 US Subaru has a transponder, so a correctly cut key starts the car. Subaru's own chart shows immobilizers arriving by model and trim from the 2005 model year. That year only the Forester XT, Impreza STi, Legacy GT and Outback XT and 3.0R had one. Every Legacy, Outback and Tribeca followed for 2006, the WRX joined the STi, the whole Impreza line had one by 2008 and the whole Forester line by 2009. The first systems use Texas 4D62 chips in side-cut keys. Subaru then moved to high-security laser-cut keys on 2008-2011 Imprezas, 2008-2014 WRX and STI models, 2009-2013 Foresters and 2010-2014 Legacy and Outback models. From the 2012 Impreza, an 80-bit Subaru G chip arrived in a side-cut remote-head key. The 2017 Impreza introduced the 128-bit Subaru H chip, which reached the Crosstrek for 2018, the Forester and Ascent for 2019 and the Legacy and Outback for 2020. Keyless Access smart keys began with the 2013 BRZ and the 2013-2014 Legacy and Outback.

• Subaru's immobilizer chart lists only the STi for 2005 and the WRX and STi for 2006-2007; other Imprezas of these years have none.
• The 2005-2007 two-button remote, FCC ID NHVWB1U711 (part 88036-FE041), is shared with the 2005-2008 Forester.

Programming a 2004 Impreza key

On chipless cars, we cut the key by code or by decoding a lock and you drive away. For a 2005-2007 STi or a 2006-2007 WRX, we cut the blade and then register the transponder through the OBD-II port, using Subaru's immobilizer data for your VIN, so a key can be made from one working key or from none. Separate fobs pair through their own routine or a scan tool. Tell us the trim when you call, because it changes the job.

Lost every key to your Impreza?

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. Entry comes before key-making because we need access to the ignition, the OBD-II port and sometimes the documents in the glove box. We take care with weather stripping, door frames and paint, and we confirm the dash VIN matches your registration before going any further.
3. Originate a new key from the car. Originating a key means building it without a sample. The door lock usually reveals most of the cuts; any it doesn't are worked out by test-cutting and trying the ignition or a second lock. The finished blade should feel like a factory key, not a forced fit.
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 Impreza 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

• 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.
• 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.
• 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.

Dealer or mobile locksmith?

Dealers have one clear advantage: direct access to the manufacturer's own systems. Some newer vehicles tie key programming to online authorization that only a dealer can use, and certain all-keys-lost situations on specific platforms still require it. A good locksmith knows where those lines are. Where we can do the job, we use professional programming equipment that talks to the same immobilizer and keyless systems through the OBD-II port, and in many cases the result is identical: a properly registered key that starts the car. Where we can't, we can often still help by opening the vehicle, cutting a mechanical blade from code, or helping you gather what the dealer will ask for so that visit goes smoothly. For your Subaru Impreza, ask us directly and you'll get a plain answer.

Impreza key battery

Most fobs for a 2004 Subaru Impreza open along a small slot in the seam; a coin or a plastic pry tool works better than a screwdriver, which chews up the housing. If the fob hides a mechanical blade, slide it out first, since the case often opens from that gap. Note which side of the old cell faces up, swap in a fresh CR2025, and press the halves together until they click all the way around. Handle the new battery by its edges, because skin oil on the faces can hurt contact. In most cases the fob keeps its programming through a battery change, so test lock, unlock and start, and you're done.

How the job works

1. Identify the exact key your Impreza 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 Subaru 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. 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 Impreza, you'll have heard that before we arrived, not halfway through the job.
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 Impreza key

• Factory or aftermarket parts. Factory keys and fobs carry the manufacturer's part number and usually the highest parts cost. Quality aftermarket keys use compatible electronics at a lower price and work well on many vehicles. We tell you which options we trust for your car, and where an aftermarket version has known range or fit issues, we steer you to OEM.
• 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.
• Blade style and cutting. The blade still matters on keyless cars, because the emergency insert has to fit the door lock. Cutting by code is standard for us. Decoding a door lock when no key or code exists adds time, and so does progressing any cuts the door lock doesn't show.
• 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

• Remote-head keys sold under FCC ID CWTB1G077 look alike but differ inside. The 2018-2019 Legacy and Outback versions carry the older G chip, while the 2017-2020 Impreza, Crosstrek, Forester and Ascent versions carry the H chip. Match the part number and pod color, not just the FCC ID.
• 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.
• If a Keyless Access fob battery dies, the car can usually still be started with the backup method in the owner's manual, which uses the fob and the start button. The emergency blade hidden in the fob opens the driver's door.

Tips from a mobile locksmith

• 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.
• 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.
• Be careful with discount fobs from online marketplaces. A listing may match your remote's shape while using a different frequency, chip or FCC ID, and many used smart keys are locked to their original vehicle. If you already bought one, send us the listing or a photo before the visit so nobody pays for a programming attempt that can't work.

Proof of ownership

Not every situation fits the simple case, so here's how we handle the common exceptions. For a leased or financed vehicle, a registration that lists you as the registered owner or lessee works with your ID. If you just bought the car, bring the signed title or bill of sale along with your ID. For a company or fleet vehicle, we need written authorization from the business plus the driver's ID. If the car belongs to a family member, the registered owner should be present or provide signed permission and a copy of their ID. Rental vehicles go through the rental company.

Need a 2004 Subaru Impreza key?

The quickest route to a working key for a 2004 Subaru Impreza starts with a short phone call. Dial (951) 903-3193, share the VIN and where the car is parked in Southern California, and we'll tell you whether it's an on-site job, a dealer job, or a mix of both. No pressure and no surprise charges, just a straight plan.