Rolling code technology is a method used in keyless entry systems, such as those used for automatic garage doors and other remote-controlled devices. It works by generating a new code each time the garage door remote control is used, which prevents unauthorized access through replay attacks.

A replay attack occurs when an attacker intercepts the code sent from the remote to the garage door opener and replays it later to gain access. However, with rolling code technology, the codes are only valid for a single use, so any replayed code will be invalid and won’t work.

The way rolling code technology works is by using an algorithm that generates a new code (out of billion possible codes) each time you use a remote device. The algorithm is based on a secret key that is shared between the remote and the opener. When the garage door remote sends a signal to the opener’s receiver, it includes the most current code generated by the algorithm. The door opener uses its algorithm to calculate the new code and compares it to the code that is received from the remote. If the codes match, access is granted.

Because the algorithm is based on a secret key, it’s impossible for an attacker to predict the next code that will be generated. This makes it very difficult for an attacker to operate your garage door and gain access to your garage. Additionally, the codes are typically only valid for a short period of time, such as a few minutes, which further limits the window of opportunity for an attacker.

How do you know if you have a rolling code garage door opener?

Most residential garage door openers started implementing rolling code technology since 1997.

Liftmaster, Chamberlain or Craftsman door openers, rolling code technology (aka Security+ 2.0 system) is available in openers with red or orange, purple, and yellow learn (or smart) button. Openers with green button, which manufactured prior to 1997, don’t use rolling code technology.

As for Genie garage door openers, rolling code technology (aka Genie Intellicode) is available in openers which don’t use deep switch technology, meaning that the opener features some type of learn (or smart) programming button.

How to reset and program a rolling code garage door opener?

Resetting the codes on your garage door opener will depend on the type of opener you have. In general, the method for resetting the opener codes is pressing and holding the opener learn (or smart) button. Once the button is pressed, the opener’s troubleshooting LED will be lit or flash, keep holding the button until the LED is off (should take approximately 30 seconds or less). The codes are now erased.

To program a remote control, press the opener’s learn button once and release. Once the opener’s troubleshooting LED is on or flashing, press the button of your choice on the remote control. Press and release in a consecutive order until the opener clicks or the door has been activated.

Universal remotes, Marantec remotes, keypads and cars may have a different programming sequence. Refer to the product’s owner manual or consult a licensed garage door repair company. Learn how to program the opener to your car.

Can you retrofit rolling code system to an older garage door opener?

You can enable rolling code on your old garage door opener by installing and setting up an external receiver which uses rolling code technology. To make sure that the opener’s signal is secured, you may want to cancel the old receiver which doesn’t use rolling code technology.