2020 Nissan Altima Key Fob Programming Guide

As a working locksmith and ASE-certified electrical technician, I see a lot of modern Nissans roll into the shop. The 2020 Nissan Altima is a fantastic car, but its push-to-start smart key system often leaves owners scratching their heads when they need a spare. Modern automotive security has come a long way, which means the days of doing a simple "key dance" in your driveway to program a remote are mostly behind us.

Here is everything you need to know about replacing, programming, and maintaining the key fob for your 2020 Nissan Altima.

Quick reference

Step-by-step on-board programming

If you are hoping to jump in your 2020 Altima, cycle the ignition a few times, and program a new smart key yourself, I have some bad news. There is no DIY on-board programming procedure for the 2020 Nissan Altima.

Nissan’s Anti-Theft System (NATS) on the newer Altima generations requires an active connection to the vehicle’s OBD2 port using specialized diagnostic equipment. The car uses a sophisticated rolling-code immobilizer system (Hitag AES transponder) to prevent theft. To add a new key, a technician must generate a PIN code specific to your vehicle's BCM (Body Control Module) and use a high-end scan tool to pair the unique signature of the new fob to the car's computer.

Attempting DIY methods found on older forums will not work on a 2020 model and can sometimes trigger an anti-theft lockout. You will need to hire a professional for the programming phase.

Battery replacement

Even though you can't program a new fob yourself, replacing a dying battery is incredibly easy and will save you a trip to the dealer. The 2020 Altima fob takes a standard CR2032 coin-cell battery.

1. Remove the emergency key: Flip the fob over and look for the small sliding latch on the back. Push it to the side and pull the metal emergency key blade straight out of the bottom.
2. Pry the shell open: Look at the slot where the emergency key just came out. You will see two small notches on either side of the center channel. Insert a small flathead screwdriver into one of these notches and gently twist to separate the two halves of the plastic shell.
3. Remove the old battery: Carefully lift the circuit board or pull the old battery directly from its housing. Note that the positive (+) side of the battery should be facing down into the back cover.
4. Insert the new battery: Pop your fresh CR2032 battery in, making sure the positive (+) side is facing the correct direction.
5. Reassemble: Line up the two halves of the key fob shell and squeeze them together until they snap tightly all the way around. Reinsert the emergency key blade.

Where to buy a replacement fob

When you need a new key, you have three main avenues, each with its own pros and cons:

• The Dealership: This is the most straightforward but most expensive route. The dealer will supply an OEM fob, cut the emergency blade, and program it. Expect to pay between $150–$250 for the fob itself, plus another $120–$180 for labor and programming. Pros: Guaranteed to work, OEM quality. Cons: Very expensive, requires an appointment and a tow if you have lost all your keys.
• A Local Automotive Locksmith: As a locksmith, this is what I do every day. We carry OEM-equivalent fobs and have the exact same programming capabilities as the dealer. The total cost is usually much lower—typically around $150–$250 total for parts, cutting, and programming. Pros: Mobile service (we come to you), more affordable than the dealer. Cons: You must ensure you hire a reputable, licensed locksmith.
• Amazon / Online Retailers: You can find aftermarket fobs online for $30–$70. Pros: Very cheap upfront cost. Cons: You still have to pay a locksmith to cut and program it (usually $75–$120). Furthermore, many locksmiths will not guarantee customer-supplied parts, as cheap internet knock-offs often have faulty transponder chips that fail during programming.

If on-board programming isn't supported

Because on-board programming isn't supported on the 2020 Altima, you have to budget for professional labor. The immobilizer system relies on a Hitag AES / NXP transponder chip embedded directly onto the remote's circuit board. When the locksmith or dealer connects their tool, they are essentially telling the car's computer, "Forget any old keys that aren't present, and authorize this new transponder chip to start the engine."

If you have lost all your keys, expect to pay a slight premium, as the technician has to originate the physical emergency key cut from scratch using the driver's door lock cylinder or a manufacturer key code, rather than simply duplicating an existing blade.

Don't let a lost key ruin your week. Find a mobile locksmith or shop on Repairius.