An entry control system includes a portable device carried by a vehicle user and a biometric sensor attached to a vehicle door. The biometric sensor includes a CCD camera and a shutter. The shutter is moved to uncover the CCD camera only when the portable device is validated. After the biometric sensor detects the biometric information based on a finger print image of the user, the shutter is moved again to cover the CCD camera. Each time the shutter moves, a brush cleans the CCD camera. The vehicle door is enabled to be opened only when the user is validated based on the biometric information.