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How Do Automatic Car Door Locks Work?


Whether they are single purpose or multi-purpose, electronic car door locks have standard features:

  • A latch/door lock
  • An actuator
  • Actuator rods
  • Activated by radio

Electric car door locks operate by receiving a radio signal transmitted by the car key fob, signaling the actuator to activate, which then routes the command through the correct path (lock/unlock) and performs the desired action.

How the actuator works

On activation, the actuator unit moves a rod attached to the rear of the latch/door lock mechanism. The rod exerts pressure on the lock-open switch on the back of the door lock mechanism. The pressure opens a pair of jaws on the latch/door lock mechanism, releasing the jaws from the strike on the center pillar.  The action connects the door handles to the latch/door lock mechanism. The door opens when you lift the an inside or outside door handle.

Computer-controlled automatic locks

A computer-controlled lock system also uses a radio signal to wake up door lock and unlock mode. The computer-controlled system sends out computer programming to the key controller module (computer). The module reads the programming that is directed its way and applies the proper system command. The computer-controlled key usually controls not only locking and unlocking doors but also auto security. The auto security piece includes car halt/disable programs that effectively make your car undrivable by potential thieves. The same system has the capability to:

  • Open the trunk lid
  • Remote start the car
  • Lower the windows
  • Kill the ignition

This system is potentially feature-rich. It depends on the amount the customer wants to spend, provided the manufacturer offers it.

One more way that automatic locks work is by keypad. Introduced 35 years ago, the keypad system appeared first in 1980 on Ford cars and trucks. Still available today, a car owner simply enters a computer code and the controller module tells the door actuator to go to work.

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

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