2025 Hyundai Tucson Key Replacement

2025 Hyundai Tucson: key facts

Key type: Smart / proximity key
Push-to-start: Yes
Transponder chip: 4A (Hitag AES)
Programming: OBD
All keys lost: We can originate new keys on site

Facelifted NX4 with smart key/push-button standard; Hitag-AES 4A fobs (95440-N9550, TQ8-FOB-4F61M43). Aftermarket 4A all-keys-lost coverage is maturing — confirmed per job.

What kind of key does the 2025 Tucson use?

The 2025 Tucson is the facelifted NX4 generation, and a smart key with push-button start is standard. There is no traditional ignition cylinder to turn. The car senses the fob nearby, and the engine starts when you press the button with your foot on the brake. Inside the fob is a Hitag AES chip, listed as the 4A family. The fob part numbers we see for this setup are 95440-N9550 and TQ8-FOB-4F61M43.

Every fob also hides a mechanical backup blade. That matters more than most owners realize. If the fob battery dies, the blade still opens the driver's door, so you are not locked out of your own car. It is a separate issue from starting the engine, though. A dead fob battery is the most common complaint on this setup, and the dash will report 'key not detected' even though the blade works fine on the door.

Before you assume you need a new key, replace the fob battery. If the message goes away, you saved yourself a replacement. If it does not, or the fob is physically damaged, that is when we come in.

Key type: smart proximity fob with push-button start
Chip: Hitag AES, 4A family
Programming method: through the OBD port
Backup: built-in mechanical emergency blade

Duplicate a key or replace after losing every key?

These are two different jobs, and the difference is real on a 2025 Tucson. Making an additional fob while you still have a working one is the simpler situation. An original key is needed for duplication on this setup, so the working fob is what lets us add another one to the car.

If every fob is gone, it is called all keys lost. It is possible on this vehicle, and we do it with professional programming through the OBD port. It takes more work because there is no working key to learn from. The car has to be told to accept a brand-new fob from scratch. One honest note: aftermarket coverage for 4A Hitag AES all-keys-lost is still maturing, so we confirm what is possible on your specific Tucson before we start rather than promise it over the phone.

If you are down to one fob, do not wait until it fails. Copying from a working key is the easier path. Losing the last one puts you in the harder job.

How we handle a 2025 Tucson fob replacement

The process is straightforward. Here is what happens when you call.

You call (213) 577-1366 and tell us the year, model, and how many working fobs you have, if any.
We confirm the VIN and the fob type your Tucson uses, so the replacement matches the car.
You come to our Westwood storefront at 10740 Wilshire Blvd, or we send a mobile van to where the Tucson is parked.
We cut or check the backup blade if needed, then program the new fob through the OBD port.
We test the fob: door lock and unlock, buttons, push-button start, and the emergency blade.

Locked out or need a locksmith now?

We answer around the clock, every day of the year.

Call (213) 577-1366

What affects the cost of a Tucson key replacement?

A smart key costs more than an old bladed key. There is no way around that. The fob is a small electronic device with an encrypted chip, and programming it takes specialized equipment. Several things move the final cost:

We explain the cost factors before any work starts, so there are no surprises when the job is done. If a new battery or a shell repair is all you need, we will say so, and that is usually the more economical route.

Whether you have a working original fob to copy from or all keys are lost
The fob itself, since the correct 4A Hitag AES unit has to be sourced
How much programming work the car requires
Whether we come to you with a mobile van or you visit the storefront
Whether the real problem is a worn button or cracked shell rather than a failed key

What we confirm, and why call us

Our data on the 2025 Tucson's chip family is verified, but all-keys-lost coverage is the one area we treat carefully. We confirm by VIN and in person before committing, because trims and build details can differ and we would rather tell you plainly than guess.

Wilshire Lock & Key has been in business since 1987. We are one company with a storefront and our own mobile vans, not a dispatch service passing your call to a stranger. David, the owner and lead technician, oversees the work. California requires locksmith companies to hold a BSIS LCO license, and you should ask any locksmith for it before they touch your car.

Other model years and trims may differ, so see the Hyundai Tucson key guide or the wider Hyundai key replacement page. For all makes, start at our car keys overview. If you want to describe your situation, use the contact page.

Frequently asked questions

Does the 2025 Hyundai Tucson use a push-button start?

Yes. The 2025 Tucson comes with a smart proximity key and push-button start as standard. The car detects the fob nearby, so you do not insert a key into an ignition.

My Tucson says 'key not detected'. Do I need a new key?

Not necessarily. A dead fob battery is a common cause. The mechanical blade inside the fob can still open the door while the dash shows that message. Try a fresh battery first. If the message stays, call us.

Can you make a key if I lost every fob?

All keys lost is possible on this Tucson through professional OBD programming. Aftermarket coverage for this chip family is still maturing, so we confirm what works on your vehicle by VIN before starting.

Do I need an original key to make a duplicate?

Yes, for duplication an original key is needed on this setup. If you still have one working fob, it is worth making a spare now. Once none are left, the job becomes an all-keys-lost replacement.

What chip does the 2025 Tucson fob use?

It uses a Hitag AES chip in the 4A family. Fob part numbers we see for this setup include 95440-N9550 and TQ8-FOB-4F61M43, and we verify the match to your car before ordering.

Can you come to me, or do I have to bring the car in?

Either works. We have a storefront at 10740 Wilshire Blvd in Los Angeles and mobile service vans. Call (213) 577-1366, any hour of the day, and we will work out which suits your situation.

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Reviewed by David, Owner & Lead Technician, Wilshire Lock & Key — in the locksmith trade since 1987.

Last updated 2026-10-11.