2016 Chrysler 300 Key Replacement

2016 300 key specs

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.

What's specific to the 2016 300

The 2016 Chrysler 300 is the sixth of 8 model years in the 300 LD (2nd generation, ID46 smart key) (2011–2018), so it shares its key system with the rest of that run, which makes replacement parts easy to source.

At roughly 10 years old, a 2016 Chrysler 300 has usually seen real wear. Fob cases crack, buttons wear through and solder joints loosen at this age, so a new shell or a replacement remote often beats repairing the old one. Many have changed hands more than once, so erasing keys you can't account for is worth doing during the visit.

Key options for the 2016 Chrysler 300

• Smart proximity key (push-to-start). A smart or proximity key lets a 2016 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.

How the Chrysler immobilizer works on the 300

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.

• From 2018 the 300 has a secure gateway module, and aftermarket programmers need a bypass cable or authenticated login to finish key work.
• The 2015 refresh changed styling and the interior but kept the M3N-40821302 ID46 smart key through 2018.
• Supplier fitment lists the same fob for the 2011–2018 Charger and 2015–2018 Challenger, but each fob must be programmed to its own car.

Programming a 2016 300 key

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.

Lost every key to your 300?

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 Chrysler 300 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 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. 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 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.
• 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.
• 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.

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 2016 Chrysler 300 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.

300 key battery

If a new CR2032 doesn't bring the fob back, the battery wasn't the problem. Common culprits include a battery holder whose solder joints have cracked from drops, contacts corroded by moisture, worn rubber button pads that no longer reach the circuit, or a board damaged by water. We can test whether the fob is transmitting at all and inspect the board closely. Sometimes a new shell or a resoldered holder solves it; sometimes the fob has to be replaced and programmed. Meanwhile, the car can usually still be started with the fob held at the backup spot described in the owner's manual.

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. If you still have a working key, we can read its cuts directly and check them against the factory depths for the Chrysler 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. 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 300, 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 a 300 key

• The type of key. Price follows complexity. The more the key does, the more it costs to replace: brass blade, then chip, then remote buttons, then full keyless entry and push-button start. If your 300 came with different key styles by trim, the one your car actually uses is the one that sets the quote.
• 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.
• Blade style and cutting. Traditional edge-cut blades are quick to cut. High-security laser-cut blades, with a groove milled into the side, need a specialized machine and more care, and the blanks themselves cost more. If we have to decode a lock to find the cuts, that adds labor as well.
• Travel, timing and extra repairs. Because we come to you, the distance from our San Bernardino base and the time of the call play a part. So does anything we find along the way, such as a worn ignition cylinder or a seized door lock. You hear about each item and get a quote before we start work.

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

Common Chrysler key problems

• 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.
• 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.
• 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.

Tips from a mobile locksmith

• 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.
• 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.
• 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.

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 2016 Chrysler 300 key?

Don't wait until the last key disappears. If your Chrysler 300 is down to one key, or the one you have is falling apart, call (951) 903-3193. We're a licensed California locksmith, license LCO7891, serving Southern California and the rest of the Inland Empire with mobile car key service every day from 6:30 a.m. to 11:30 p.m.