How to Make Your Own Tesla Key Fob From Key Card

Photo: u/TrevCostales

One user has made new hardware for his Tesla, so he doesn’t need to carry around a key card any longer.

San Francisco-based Reddit user u/TrevCostales fabricated his own Tesla key fob, including detailed, step-by-step instructions (via prior instructions from u/andy2na). Within the post’s description, as shared on the Tesla Motors subreddit, the user explains that he doesn’t normally carry a wallet, so the normal key cards aren’t particularly convenient for him.

Using epoxy, acetone, an RFID chip and antenna from Tesla’s key cards, the user coiled the antenna to fit into a generic key fob, then sealed it off so it would fit within the plastic housing.

Photo: u/TrevCostales

The user was then able to use the car to detect the key fob using his Tesla car, while simply keeping the key fob in his key chain.

Photo: u/TrevCostales

The end result simply looks like a generic key fob one would get from any automaker, perhaps with a little bit more wear-and-tear “character” from the process of putting it together.

Photo: u/TrevCostales

Here are the full DIY instructions below:

  • You’ll need new key cards, key fobs, epoxy, and acetone.

  • I recommend buying new key cards. If you mess up your originals, you’ll have no way to add or remove key cards and phones.

  • Add the new key cards to your car. I suggest doing this first before you mangle the key cards. It will be easier to check the key fob if it’s already been added.

  • Place the key cards in acetone.

  • Remove the existing chip and antenna from the fob.

  • After about a couple of hours, remove the RFID chip and antenna from the key cards.

  • Coil the antenna by twisting and folding. This is the orientation I found that will work. Other methods of coiling resulted in the car not being able to detect the RFID chip.

  • Place the coiled RFID chip and antenna into the new key fob.

  • Before sealing the key fob, test that the car will detect it.

  • Bring up the lock screen while moving the fob around the console. When it detects it, the key will move to the top, change to bold type, and show “Active.”

  • Seal the key fob using epoxy.

Tesla fans have shown their creative prowess through a number of impressive DIY projects, in the past, including this working paper mache Supercharger and more recently, this retractable automatic charging arm, among a number of others.