2016 Toyota Mirai Key Replacement

2016 Mirai key specs

First-generation Mirais use a four-button proximity fob with lock, unlock, trunk and panic buttons; catalogs list FCC HYQ14FBA under Toyota part 89904-62020. Touching the door handle with the fob nearby unlocks the car, and the POWER button starts the fuel-cell system whenever the fob is inside. An emergency blade slides out of the fob for the driver's door. There is no key slot or conventional ignition anywhere on the car.

What's specific to the 2016 Mirai

2016 was the first model year of the Mirai JPD10 (1st generation). Early-production cars sometimes use different part numbers than later ones, so for a 2016 Toyota Mirai we confirm the exact key from the VIN or the old key's FCC ID before cutting anything.

At roughly 10 years old, a 2016 Toyota Mirai 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 Toyota Mirai

• Smart proximity key (push-to-start). A smart or proximity key lets a 2016 Toyota Mirai 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 Toyota immobilizer works on the Mirai

Toyota phased in transponder immobilizers model by model, so two Toyotas from the same year can need very different keys. Starting with the 1998 model year, the Camry, Avalon, 4Runner, Sienna and Land Cruiser used a fixed-code Texas 4C chip, while US Corollas, the Echo and other economy models kept plain mechanical keys into the mid-2000s. Between 2003 and 2005, depending on the model, the encrypted Texas 4D-67 chip took over. Around 2010 came the 80-bit G chip, and from about 2014 the 128-bit H chip, also called 8A. Many of these later keys carry a stamped D, G or H on the blade. Smart keys spread to US Toyotas with cars like the 2004 Prius, 2005 Avalon and 2007 Camry, moved to 128-bit fobs in the 2010s, and since about 2022 Toyota has used a newer generation: Texas 8A BA-type fobs in models such as the bZ4X and Crown, and NXP Hitag AES, often called 4A, in the Corolla, Corolla Cross and 2025 Camry. Partner-built cars follow their partner's rules, so the 86 and GR86 use Subaru systems and the GR Supra uses BMW's. The letter on your blade, the FCC ID on your fob and your VIN tell us which system we are working with.

• Toyota began US retail deliveries of the Mirai in California in October 2015, as a 2016 model.
• Its HYQ14FBA fob is a four-button version with a trunk button, part 89904-62020, not the Highlander's fob with the same FCC ID.
• With a dead fob battery, the car can still be started by touching the POWER button with the fob's Toyota emblem side, per Toyota's procedure.

Programming a 2016 Mirai key

There is no on-board programming for Mirai fobs. A new fob is registered with a programmer through the OBD-II port and the smart key system, after which the emergency blade is cut to the door lock. Aftermarket tool coverage for the Mirai is thinner than for the Prius or Camry because so few were sold, so we check your VIN against our equipment before scheduling. All-keys-lost may require direct access to the smart key ECU or a visit to a Toyota fuel-cell dealer.

Adding a fob is often possible with current tools. All-keys-lost on this low-volume car may need smart key ECU access or a Toyota fuel-cell dealer.

Lost every key to your Mirai?

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 Toyota Mirai 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. 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 Toyota Mirai 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

• 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.
• 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.
• 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?

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 Toyota Mirai 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.

Mirai key battery

If a new replacement 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 Mirai 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 Toyota 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 Mirai, 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 Mirai 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 Toyota Mirai is the most involved of all, both in the part itself and in the programming.
• 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 Toyota system adds equipment time and labor to the job.
• 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 Toyota key problems

• Remote-head keys take a beating on a key ring: the plastic head cracks and the rubber button pad tears. The chip and circuit board usually survive, so a new shell and freshly cut blade often fix the problem.
• Toyota chip keys are easy to mix up. Many later keys are stamped near the head with D for the 4D-67 chip, G for the 80-bit G chip or H for the 128-bit H chip, and a key ordered by looks alone often won't program.
• Toyota smart keys look alike across models but carry different FCC IDs and board numbers. Suppliers warn, for example, that a 2007-2010 fob with an E board won't substitute for one with a numbered 0140 board.

Tips from a mobile locksmith

• If your vehicle has a proximity key, think about where it sleeps at night. A fob hanging by the front door can sit within range of relay equipment used to open and start cars from outside. A drawer deeper inside the house, a signal-blocking pouch, or the fob's own sleep mode reduces that risk considerably.
• 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.
• 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 2016 Toyota Mirai key?

Locked out, keyless, or just tired of a fob that only works half the time? Julian's Locksmith can help with your Mirai in Southern California. Have your registration and photo ID ready, call (951) 903-3193, and we'll give you an honest answer about what we can do on-site and what it will cost before we head your way.