Most cars have dashboard clocks and the majority of these are LCD digital clocks. Digital clocks combine two types of technology.

In the first of these technologies, the oscillator, which is needed to make all clocks, including a digital LCD clock, function, is normally provided by a crystal. An electrical charge is passed through the crystal, which causes its shape to alter and make it release a slight noise, at a regular frequency. This sound is converted into an electronic signal. Through the employment of a series of counters, the oscillations, which are connected to an electronic chip, send a signal to the display which uses lights to display the time.

The second piece of technology is the display. LCD stands for Liquid Crystal Display and utilises two thin sheets of polarizing material. These sheets have a liquid crystal solution between them. When an electric current crosses the liquid, these crystals fall into alignment, preventing any light from passing through them. Each crystal, therefore, acts as if it is a curtain that can either allow light to pass though or prevent it from doing so. The light that passes through the face of a digital LCD clock in a motor vehicle is what displays the time.

A clock may seem like a simple accessory, but the LCD digital clock is a sophisticated motor part.