Technology has advanced for automotive security and user-focused features, and a shift is occurring where traditional key-and-cylinder starting systems are being replaced by keyless push-button ignition systems. They are incredibly simple to operate and provide excellent security.
The system was developed initially in the mid-1990’s by Siemens and was released first in Mercedes-Benz vehicles as Keyless Go. Since then, their popularity has grown exponentially. Now, keyless push-button ignition systems are known by dozens of different names depending on the auto manufacturer, including:
- SMART Key
- Keyless Go
- FAST Key
- Intelligent Key
- Comfort Access
How it Works
Keyless push-button ignition operates based on low-frequency radio ID. Your key fob is a transmitter equipped with a specific electronic ID tag and the signal is amplified with a battery in the key fob. When you are in close proximity to your vehicle, antennas around your vehicle recognize your key fob’s presence and allow you to unlock and lock your doors with the press of a button on the handle, if it is so equipped.
When you enter your car, the antennas around your vehicle make comparative calculations to determine that you are indeed inside. The antennas transmit the electronic ID from the key fob to the receiver module. When you press the ignition button to start the car, the receiver disables the immobilizer, powers the starter circuit, and the engine turns over.
If the key fob battery is dead, you may not be able to unlock your doors or start your car in the same fashion. Manufacturers typically include a backup source to start your car such as a key shaft hidden in the fob. There is a location in the dash it needs to be inserted where another antenna or transponder ring picks up the diminished signal and allows the car to start.
If you lose your key fob, your car will not be able to start at all. You will need to have a new key made in order to use your car again.
This article originally appeared on YourMechanic.com as How a Keyless Push-Button Ignition Works and was authored by Jason Unrau.