Skip the auto shop - Our mechanics make house calls

How a Keyless Push-Button Ignition Works

Keyless Ignition Works

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.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

More related articles

How Long Does a Throttle Return Spring Last?
Not all vehicles on the road feature an electronic throttle control (ETC), which is also called drive-by-wire. For vehicles that don't offer this system, they have a throttle cable instead that...
How to Find the Keyless Code on a Ford Explorer or Mercury Mountaineer
Many Ford Explorers and Mercury Mountaineers were manufactured with an option known as the Ford keyless entry keypad. Some models refer to it as SecuriCode as well. It...
How to Transfer a Car Title in Idaho
In order to prove ownership of a car, you must have the title. However, when a car is sold, given away or inherited, the title needs...


Related questions

Q: Alarm and keyless entry malfunction, G error code

Hey there, thanks for writing in about your 2007 Mercedes Benz E550. The car alarm in many of the later model Mercedes vehicles has it's own set of small batteries. When these batteries go bad, they will automatically set off the...

Q: car completely died going down road now won't start

Hello there, without knowing your make and model I can only provide a very basic answer. Touching the ignition switch wires together to start the car will cause long term damage and can damage the wiring harness. Many common faults...

Q: 2004 Ford Ranger doesn't turn off when key is removed

The problem is likely a bad ignition switch. The ignition switch routes power to the entire vehicle including the accessories, computers, fuel and ignition system. Basically, the failed switch is allowing the vehicle to stay on. A professional, such as...