Keyless Entry Radar (Image Courtesy: Toyota)

Keyless Entry & Smart Key: What does Keyless Entry mean?

 | 4 minutes read

What is Keyless Entry?

Keyless Entry or Passive Entry is a terminology commonly used in an automotive technology, which locks and unlocks a vehicle without using a conventional key and/or pressing the buttons on the Remote / Smart Key.  However, Keyless Entry DOES NOT mean that ‘there is no key’. Rather, it means that ‘there is NO need’ to physically enter the conventional (metal) key into the lock/ignition as was the case in the earlier generation cars.

When you enter the vehicle with a Keyless Entry / Smart Key, you can start/stop the engine, without actually inserting the car key into the ignition switch. A built-in transponder of the Smart Key identifies the vehicle to which it is ‘associated’ and automatically activates its ignition. As a safety measure, a vehicle cannot be locked so long as its Smart Key remains inside that vehicle. However, Bosch is going ahead when it comes to technology. Bosch recently showcased new technology to the world called Bosch Perfectly Keyless.

What is a Smart Key?

The Smart Key is a sophisticated, ‘computerized’ key; which accesses and unlocks the car’s locking system electronically. It replaces the conventional / metal key in modern day cars. Siemens developed the electronic Smart Key system in the 90s, while Mercedes-Benz used it first on its S-Class in 1998 under the trade-name "Keyless Go".

Smart Key (Image Courtesy: Mercedes Benz)
Smart Key (Image Courtesy: Mercedes Benz)

With the Smart Key kept in the pocket, the driver can lock/unlock and start the vehicle. The vehicle identifies its own Smart Key from the radio pulse generator in the key housing, which detects the radio signal thru’ one of the many antennas fitted around the vehicle. One can unlock the vehicle, by simply pressing a button or sensor fitted on the door handle. Additionally, the Smart Key system comes with a Start-Stop switch. In case of loss of the Smart Key, you can still unlock the car with a spare key-blade (without electronic circuitry) supplied by the manufacturer.

The Smart key can unlock the immobilizer and turn-on the ignition without inserting the key in the ignition switch; so long as it remains inside the car. When you enter the vehicle with the Smart Key in your pocket, you can start the engine by simply pressing the Start-Stop button.

Mercedes uses the Smart Key & Start-Stop button (Image Courtesy: Mercedes Benz)
Mercedes' engine can be started by both the Smart Key & Start-Stop button (Image Courtesy: Mercedes Benz)

By keeping the Smart Key in your pocket, you can lock the car using different methods (which differ from models to models) such as either by:

  1. Pressing a button on the door handle, OR
  2. Touching a capacitive area on a door handle, OR
  3. Walking away from the vehicle
Door Handle with button (Image Courtesy: Mercedes Benz)
Door Handle with button (Image Courtesy: Mercedes Benz)

In some advanced versions, the system automatically adjusts the settings to suit the last user; who operated the Smart Key to unlock the car. It can also remember user preferences; such as seat and steering wheel positions, exterior mirror settings, A/c cabin temperature music system, and audio volume levels etc. In some more advanced options, you can even customize the other Smart Key to restrict vehicle's pre-set speed. This is very useful, in case someone; such as a teen-aged child, uses that key to start/drive the car.

Comfort Access System (Image Courtesy: BMW)
Comfort Access System (Image Courtesy: BMW)

How to use Keyless Entry / Smart Key?

When Starting the engine with Automatic gearbox:

  1. Keep the Smart Key in the pocket, and enter the vehicle.
  2. Make sure that gear lever is in "P" (Park) position.
  3. Press the Brake Pedal
  4. Push the Start-Stop Button
  5. Engine Starts


When Starting the engine with Manual gearbox:

  1. Press the clutch & move gear-lever to neutral.
  2. Press Brake Pedal.
  3. Push Engine Start Button.
  4. Engine Starts.

When Stopping the engine:

Automatic gearbox:

  1. Put gear lever in "P" position. (Automatic gearbox)
  2. Press Start-Stop Button.

Manual gearbox:

  1. Press clutch & move gear-lever to neutral.
  2. Press Start-Stop Button.

When operating the ACC mode:

  1. Press Engine Start-Stop button without pressing Brake Pedal.
  2. Use electric devices such as radio in ACC mode.

Watch Keyless Entry video here:

Read More: What is Start-Stop System?>>

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