2024 Nissan Altima Key Fob Programming & Replacement Guide

As a locksmith and ASE-certified electrical technician, I get asked about key fob programming for modern vehicles every day. The 2024 Nissan Altima is a fantastic car, but its advanced security features mean that dealing with key fobs isn't quite as simple as it was in the early 2000s. The 2024 Altima utilizes a push-to-start proximity smart key system, which heavily integrates with the vehicle’s Body Control Module (BCM) and immobilizer network.

Here is everything you need to know about replacing, repairing, and programming your 2024 Nissan Altima key fob.

Quick reference

Step-by-step on-board programming

If you are looking for a magical sequence of turning the ignition on and off, opening the door, or pressing the brake pedal to program your 2024 Nissan Altima fob, I have some bad news. There is no DIY on-board programming procedure for the 2024 Nissan Altima.

Nissan’s modern push-to-start systems use advanced rolling-code transponders (Hitag AES) designed to prevent vehicle theft. Because of this, adding or erasing a key fob requires connecting a specialized bi-directional scan tool or key programmer to the vehicle's OBD2 port.

To program a new key, a professional must:

1. Connect their programming tablet to the Altima's OBD2 port.
2. Read the vehicle's BCM PIN code (a security measure to prevent unauthorized access).
3. Bypass the security gateway to access the immobilizer module.
4. Wipe the old keys (if lost) or enter "Add Key" mode.
5. Hold the new smart key up to the push-to-start button to pair the transponder chip.

Because this requires equipment costing thousands of dollars, you will need to hire a professional to program any new fob to this vehicle.

Battery replacement

While you can't program the remote yourself, changing a dead battery is a very simple DIY task. The 2024 Altima smart key uses a standard CR2032 coin-cell battery.

1. Remove the emergency key: Flip the fob over and slide the small latch on the back to release the metal emergency key blade. Pull it out.
2. Pry the shell apart: Look at the slot where the emergency key used to be. You will see two small notches on the sides of the slot. Insert a small flathead screwdriver into one of the notches and gently twist to pop the two halves of the plastic shell apart.
3. Remove the old battery: Carefully lift the circuit board or pry the old battery out of its housing. Make note of which way the battery is facing (usually positive "+" side facing down in the back shell).
4. Insert the new CR2032: Place the new battery in the exact same orientation.
5. Reassemble: Snap the two halves of the plastic shell back together firmly. Reinsert the metal emergency key.

Where to buy a replacement fob

When buying a replacement smart key for your Altima, you have three main options:

• The Dealership: Going to the local Nissan dealer is the most straightforward route. You are guaranteed to get an OEM fob (PN 285E3-6CA1A). However, this is the most expensive route. Expect to pay anywhere from $250 to $400 for the fob, the emergency blade cut, and the programming labor.
• An Automotive Locksmith: A specialized auto locksmith can provide either an OEM fob or a high-quality aftermarket option like Keyless2Go. The major pro here is cost and convenience; locksmiths are usually 20% to 40% cheaper than the dealer, and mobile locksmiths will come directly to your driveway. Expect to pay $180 to $280 total.
• Amazon / eBay: You can buy extremely cheap aftermarket fobs online for $20 to $50. While this seems like a great deal, it carries risks. Many online fobs have inferior circuit boards that fail quickly or refuse to program. Furthermore, you will still have to pay a locksmith $80 to $150 to cut the emergency blade and program the fob to your car.

If on-board programming isn't supported

As mentioned, you cannot program this key yourself. The push-to-start immobilizer requires an active handshake with the fob to authorize the engine to start. Even if you purchase a fob online with the correct FCC ID (KR5TXN1), the car will completely ignore it until the BCM has been instructed to accept its unique digital signature via an OBD2 scan tool.

When budgeting for a lost key situation, factor in the programming fee. If you have lost all your keys, expect the cost to be higher, as the technician will have to start from scratch rather than simply cloning or adding an active key.

Find a mobile locksmith or shop on Repairius.