Chrysler 300 Key Replacement

300 keys by generation

For 2019 the 300 kept the same fob shape but moved to a Hitag AES transponder and a new FCC ID, M3M-40821302, so a 2018 fob will not program to a 2019 car even though the two look alike. Buttons are lock, unlock, trunk and panic, with remote start on equipped cars, and the emergency blade slides out of the case. The final 2023 model year included a 300C with the 6.4-liter V8, and its key follows the same pattern. These cars combine the AES fob with the secure gateway module, so programming needs a current tool, a gateway bypass or authenticated connection, and the vehicle PIN. Adding a spare to a car with a working fob is usually straightforward. With every fob lost, some cars can be done over OBD-II and others need the radio frequency hub handled on the bench or a dealer visit, so we confirm by VIN first.

The redesigned 300 went to proximity entry and push-button start, and most supplier listings show smart keys for these years. The fob has four buttons (lock, unlock, trunk, panic), or five with remote start, and a release on the side frees an emergency blade for the driver's door. Through 2018 it is listed under FCC ID M3N-40821302 with a Philips ID46 (Hitag2) chip, the same unit used on the Dodge Charger of those years. A few catalogs also list the older fobik-style proximity fob, IYZ-C01C, for some 2011–2015 cars, so match the FCC ID on your original. New smart keys are programmed through the OBD-II port with a tool that obtains the 4-digit PIN and writes the fob to the car's radio frequency hub. Adding a key and all-keys-lost follow nearly the same path, since no blade has to start the engine. On 2018 cars the factory secure gateway module blocks many aftermarket tools from writing data, so a bypass cable or authenticated access becomes part of the job.

For 2008 the 300 switched to Chrysler's fobik: a blade-less remote that you push into a dash-mounted wireless ignition node and twist. The fob holds lock, unlock, trunk and panic buttons, a remote-start button on equipped cars, and a small emergency key for the door. Some cars were built with Keyless Enter 'n Go, which uses a proximity version of the same fob. Replacements are listed under FCC ID IYZ-C01C (also printed as M3N5WY783X) at 433 MHz, with a Philips ID46 chip in both versions. The wireless ignition node (WIN) holds the immobilizer, and new fobiks are added through the OBD-II port using the 4-digit PIN. Cars built before 2011 can sometimes learn an extra fobik on board when two working fobs already start the engine. A fobik is never cut, so all-keys-lost on these cars is mostly an electronic job: we obtain the PIN, program new fobiks, and cut the small emergency insert for the door.

Early LX cars, including the 300C and SRT8, came with a four-button remote-head key: lock, unlock, trunk and panic buttons in the head of a transponder key cut for the Y159 keyway. The factory remote is listed under FCC ID KOBDT04A at 315 MHz, and some cars carry OHT692715AA or the OHT692427AA family instead, all with a Philips ID46 chip. A plain buttonless transponder key is also catalogued. Shell catalogs separate the 2005–2006 and 2007 head styles, so match the shape when ordering. Keys are programmed through the OBD-II port with the 4-digit security PIN, using a tool that supports this platform, and the chip and the remote buttons can need separate steps. Many Chrysler owner's manuals of this era describe a key-learn routine that needs two working keys, which is no help once you are down to one. With all keys lost, we cut a blade by code or from a decoded lock, obtain the PIN, and program new keys at the car.

Chrysler key security

Chrysler began fitting its Sentry Key Immobilizer System (SKIS) in the late 1990s, and by the 2001 model year most Chryslers in our range used it. The first wave of keys carried a Texas Instruments 4D64 chip in a head cut for the Y159-family keyway, sold as the Ilco Y160-PT blank. From about 2004 the chip changed to a Philips ID46, and most cars paired it with a remote-head key that put the transponder and the keyless entry buttons in one piece. For 2008 the 300 and Town & Country moved to the fobik, a blade-less remote that turns inside a wireless ignition node (WIN), with a proximity version for push-button start. The 2011 redesign of the 300 added a proximity smart key, and the Pacifica minivan, the 2015–2017 200 and the 2019–2023 300 use fobs with Hitag AES encryption. Vehicles from 2018 on also carry a secure gateway module that limits what aftermarket tools can write. Two models break the pattern: the Mitsubishi-built Sebring coupe uses a 4D61 chip and a Mitsubishi blade, and the Mercedes-based Crossfire uses an HU64 flip key with Mercedes immobilizer electronics.

Most Chrysler key work runs through the OBD-II port and a 4-digit security PIN tied to the vehicle. Current programmers can read that PIN from the immobilizer on many older models; on others it comes from the dealer by VIN, which requires proof of ownership. Many cars through about 2010 also have an owner-level key-learn routine, but it needs two working keys already in hand, so it is no help once you are down to one or none. A remote-head key can need the chip and the buttons learned in separate steps, so a key that starts the engine may still need its remote side set up. Most 2011 and newer remotes need a programming tool. On 2018 and newer vehicles, the secure gateway module adds a bypass cable or authenticated login to every job. Before we cut or program anything we verify your ID and ownership, and we quote the whole job, including key, cutting and programming, before starting.

All 300 keys lost

Losing every key is usually recoverable on a Chrysler without towing it to a dealer. For bladed keys, we decode a door lock or cut by code from the VIN record after confirming you own the vehicle, then program a new transponder or remote-head key through the OBD-II port. Fobik-equipped vans and sedans need no ignition cut, so that work is mostly electronic plus a new emergency insert for the door. The harder cases are the AES-encrypted smart keys on the Pacifica, Voyager, 2015–2017 200 and 2019–2023 300, where some vehicles need the radio frequency hub handled directly or a dealer visit, and the Crossfire, whose Mercedes-derived keys are normally ordered pre-coded. We tell you which case applies before we drive out.

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. 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 Chrysler 300 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.

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 Chrysler 300, ask us directly and you'll get a plain answer.

How the job works

1. Identify the exact key your 300 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. California holds licensed locksmiths responsible for knowing whose car they're making keys for. We record your name, the VIN and the plate on a work order. If you aren't the registered owner, you'll need the owner's written authorization along with your own photo ID before we begin.
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. With the blade done, we connect to the OBD-II port and register the new key with the immobilizer. Depending on the Chrysler 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. 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 300 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 Chrysler 300 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.
• 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 Chrysler 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.

300 key types explained

• 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 2023 Chrysler 300 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.
• Remote head key. Remote-head keys take a beating. The rubber button pad wears through, the plastic housing splits at the seam, and the blade can snap right at the head after years of being used as a pry tool or hanging from a heavy key ring. When the electronics inside are still healthy, we can often move the circuit board and chip into a new shell and cut a fresh blade to your code, which keeps the existing programming intact. If the board is cracked or water-damaged, a new key is the honest answer. Either way, for your 2023 300, we open the old key and show you what's broken before recommending anything.
• Smart proximity key (push-to-start). A smart or proximity key lets a 2023 Chrysler 300 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 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.

Tips from a mobile locksmith

• 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.
• 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.

Common Chrysler key problems

• Worn Y159 ignition keys on older minivans, PT Cruisers and LH sedans can stop turning smoothly or bind in the cylinder. Copying a worn key copies the wear, so we cut replacements to the original code rather than tracing the old blade.
• On 2008–2016 Town & Country vans and 2008–2010 300s, a fobik that will not turn or is not recognized may be a worn fob or a failing wireless ignition node. We test with a known-good fob before anyone replaces parts.
• Remote-head keys from the 2004–2014 era often crack where the blade meets the plastic head. A new shell can save the electronics, but the transponder chip has to move with them or the car will not stay running.
• A remote that only works from a few feet away usually needs a fresh battery. Fobs from 1999–2006 use CR2016 coin cells, while most later remote-head keys, fobiks and smart keys take a single CR2032. Inland summer heat is hard on these cells, so the battery is the first check.
• Remotes bought online for 2004 and later Chryslers still have to be paired to the car. Some cars through about 2010 can learn one at home if you hold two working keys; otherwise it takes a programming tool, and used fobs must be unlocked first.
• On 2018 and newer Chryslers, the secure gateway module blocks many aftermarket scan tools. Key programming still works with a bypass cable or authenticated access, which is why a shop without that setup may tell you only the dealer can help.
• The 2018 and 2019 Chrysler 300 smart keys look identical but carry different transponder chips and different FCC IDs, M3N-40821302 versus M3M-40821302. Ordering by appearance alone leads to a fob that will not program, so match the model year and part number.
• Sebring orders get mixed up often: the sedan and convertible use Chrysler keys and fobs, while the 2001–2005 Sebring coupe uses Mitsubishi-based keys and remotes that fit none of the other Sebrings.

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.