2020 Toyota Tundra Key Fob Programming Guide

Quick reference

Step-by-step on-board programming

Unfortunately, for the 2020 Toyota Tundra, there is no on-board (DIY) programming procedure available for new key fobs. This is a significant change from older Toyota models where you could perform a sequence of actions like opening and closing doors and cycling the ignition to pair a new remote.

Starting around 2018 for most of its lineup, Toyota transitioned to a more secure system that requires specialized diagnostic tools to program new keys. This is primarily to enhance the vehicle's security and make it more difficult for unauthorized individuals to create a working key for your truck.

To program a new key fob for your 2020 Tundra, you will need to use a professional-grade automotive scan tool, such as Toyota's own Techstream software or other high-end tools available to automotive locksmiths and repair shops. These tools communicate directly with the vehicle's immobilizer and body control modules to authorize and add the new fob to the system's memory.

Therefore, programming for this vehicle must be done by a Toyota dealership or a qualified automotive locksmith.

Battery replacement

If your key fob's range is decreasing or it's working intermittently, the first and easiest thing to check is the battery. The 2020 Tundra fob uses a single CR2032 lithium coin battery.

Here’s how to replace it:

1. Release the emergency key: Look for a small release button or latch on the side or back of the fob. Slide it and pull out the metal emergency key blade.
2. Open the case: Insert the tip of the emergency key (or a small flathead screwdriver) into the slot it came from. Gently twist to pry the two halves of the fob case apart. Be careful not to apply excessive force, which could crack the plastic.
3. Remove the old battery: Note the orientation of the old CR2032 battery. Usually, the positive (+) side, marked with text, faces up. Gently pop it out of its holder. A small non-metallic tool can be helpful here.
4. Insert the new battery: Slide the new CR2032 battery into place, ensuring the positive (+) side is facing the correct direction.
5. Reassemble the fob: Snap the two halves of the case back together until they click securely. Re-insert the emergency key blade.

Replacing the battery does not require reprogramming the fob.

Where to buy a replacement fob

You have several options for purchasing a new key fob, each with its own pros, cons, and cost implications:

• Toyota Dealership: This is the most expensive but most straightforward option. You are guaranteed to get a genuine OEM (Original Equipment Manufacturer) fob that is correct for your vehicle's VIN. The parts and labor are warrantied. Expect to pay anywhere from $300 to $600 for the fob, key cutting, and programming service.

• Automotive Locksmith: A certified automotive locksmith is often the best balance of cost and convenience. They have access to OEM and high-quality aftermarket fobs and possess the necessary tools to cut the emergency key and program the remote. Many are mobile and can come to you. This is typically more affordable than the dealership, often in the $200 to $400 range.

• Online (Amazon, eBay, etc.): You can find fobs online for as little as $50 to $150. However, this route carries risks. You might receive a low-quality, used, or incorrect fob. Even if you buy a genuine-looking fob, it may have been previously programmed to another vehicle and be 'locked,' rendering it un-programmable. Remember that you will still need to pay a locksmith or dealer to cut and program it, and many will not work with customer-supplied parts due to these risks.

If on-board programming isn't supported

As mentioned, the 2020 Tundra requires professional tools for a reason: the immobilizer. Your key fob contains a transponder chip that the truck must recognize before it allows the engine to start. This is a critical anti-theft feature.

When a locksmith or dealer programs a new key, they aren't just pairing a remote for the locks; they are registering the unique transponder chip with the vehicle's engine control unit (ECU). Their diagnostic tool initiates a 'handshake' between the new fob and the truck's computer, securely adding it to an approved list of keys. Any key not on this list will fail to start the engine, even if it can unlock the doors.

Given the need for specialized equipment and expertise, expect to pay for 1-1.5 hours of labor for key programming at a dealership or locksmith, in addition to the cost of the fob itself and the service of cutting the physical emergency key blade.

Find a mobile locksmith or shop on Repairius.