2004 Mitsubishi Eclipse Key Replacement

2004 Eclipse key specs

Third-generation Eclipses and Spyders start with a plastic-head transponder key on the straight MIT6 blade. Supplier references list a Texas 4D60 chip for 2000 and early-2001 builds and a 4D61 chip from mid-2001 through 2005, so we read the chip before cutting. Keyless entry came as a separate remote: a two- or three-button HYQ12ABA unit on 2000-2001 cars and, from 2002, a two-, three- or four-button OUCG8D-525M-A remote. All of these remotes take a CR2032. The Spyder uses the same key and remotes as the coupe.

What's specific to the 2004 Eclipse

The 2004 Mitsubishi Eclipse is the fifth of 6 model years in the Eclipse Third generation (2000–2005), so it shares its key system with the rest of that run, which makes replacement parts easy to source. A 2004 Mitsubishi Eclipse 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 Eclipse'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 Mitsubishi Eclipse

• Transponder (chip) key. A transponder key carries a small chip in its head, usually a glass capsule or a carbon wafer, with no battery of its own. When you turn the key in a 2004 Mitsubishi Eclipse that uses one, an antenna ring around the ignition energizes the chip and asks for its code. If the answer matches what the immobilizer has stored, the engine is allowed to run. If it doesn't, you get the classic symptoms: the engine cranks but won't fire, or it fires and dies after a second, and the security light on the dash flashes or stays lit. That's why a perfectly cut copy without a programmed chip will open the doors but won't start the car.
• Key with separate remote fob. Some Mitsubishi Eclipse 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 Mitsubishi immobilizer works on the Eclipse

Mitsubishi's US key history splits into a handful of eras, and the model year usually tells us which one we're dealing with. Around 2000, the larger models got Texas Instruments transponders: the Diamante, Montero and Montero Sport on the MIT1 key, and the Eclipse and Galant on the MIT6 key, with the chip moving from 4D60 to 4D61 around the middle of 2001. Small cars such as the Mirage and the 2002-2007 Lancer generally kept plain cut keys, although the Lancer Evolution did not. Philips ID46 chips appeared on the redesigned 2004 Galant, remote-head keys followed in 2006, and the blade changed from the straight MIT6 to the shouldered MIT3 during the 2007 model year. The 2007 Outlander and 2008 Lancer introduced FAST-key, Mitsubishi's keyless operation system, which carried on through the Lancer Evolution X and the Outlander Sport. Later Mirage, Eclipse Cross and Outlander Sport smart keys are newer designs that need their own tool coverage, and the Nissan-based 2022-on Outlander uses an AES-encrypted fob. The Dodge Dakota-based Raider pickup follows Chrysler's Sentry Key rules instead.

• The 2000-2001 remote (FCC ID HYQ12ABA) is a different part from the 2002-2005 remote (FCC ID OUCG8D-525M-A).
• The Eclipse Spyder convertible joined the lineup for 2001 and shares the coupe's keys.
• Ilco's MIT13-PT key (Texas 4D61) fits the Eclipse from 2001, the Galant from 2001 to 2003 and the 2004 Endeavor.

Programming a 2004 Eclipse key

Chip keys are registered through the OBD-II port with a programmer and the immobilizer PIN; the routine erases and relearns every key, so bring all of them. The separate remotes pair on board through a jumper routine at the diagnostic connector. If every key is lost, we decode a lock, cut new MIT6 keys on the right chip blank and register them at the car.

Lost every key to your Eclipse?

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. 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. Once the car starts, we remove the lost keys from memory wherever the system allows, so they can't start the engine if someone finds them. Making a second key during the same visit costs much less than a repeat all-keys-lost call down the road.

Why a spare key pays for itself

• 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.
• 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.
• 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 Mitsubishi Eclipse, ask us directly and you'll get a plain answer.

Eclipse key battery

Battery details for the 2004 Eclipse: CR2032 (separate remote). 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 Eclipse uses. Every job starts with the VIN, the trim and a look at any key you still have. From those we confirm the keyway, the transponder or smart-key chip, the remote frequency, the FCC ID and the button layout. Two Mitsubishi Eclipse keys that look identical can carry different electronics, so this step keeps the wrong part from ever reaching the car.
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 Mitsubishi 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 Mitsubishi 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 Eclipse 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.
• 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 Mitsubishi system adds equipment time and labor to the job.
• 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 Mitsubishi key problems

• The 2007 Outlander used a one-year FAST-key fob, FCC ID OUCG8D-640M-KEY-N, that differs from the OUC644M-KEY-N fob used from 2008 on. Ordering by model name alone often brings the wrong part.
• Key registration on many Mitsubishis wipes every stored key and relearns only the ones present. A spare left at home during the appointment stops working afterward, so gather every key you want to keep before we start.
• Mitsubishi remotes and smart fobs lock to the first vehicle they're programmed to. A used one from a salvage yard or online seller has to be unlocked or reflashed before it will pair, and some newer fobs cannot be reused at all.

Tips from a mobile locksmith

• 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.
• 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.
• Every so often, use the mechanical blade in the driver's door lock. Cylinders that go years without a key can seize from dust and dried grease, and you won't find out until the day the fob dies and the blade is your only way in. A small shot of dry lubricant keeps the lock ready.

Proof of ownership

Before we cut or program a key for any vehicle, we verify that you have the right to it. Please have two things ready: the current registration or the title, and a government-issued photo ID with a matching name. We also check that the VIN on those documents matches the VIN plate on the dashboard. If the registration is locked inside the car, that's fine; we open the vehicle first, check the paperwork in the glove box, and only then make the key. If something doesn't line up, we stop and sort it out before any key is made.

Need a 2004 Mitsubishi Eclipse key?

Need a key for your 2004 Mitsubishi Eclipse? 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.