Tell-tale (automotive)

Idiot lights

An idiot light is a method of displaying information about a system (e.g. an engine, or a piece of factory equipment). Usually found in display panels, such as an automobile dashboard, they consist of an illumination source (usually an incandescent light bulb or an LED) with some form of explanatory symbol or textual label. The usual method of operation is that the condition indicated is in effect when the light is lit. Using the dashboard example, a commonly found idiot light on modern cars is the "check engine" light, which is usually an orange light overlaid with a symbolic representation of an engine. Another perhaps more fitting example of an "idiot light" is an oil warning indicator in an automobile. In such a system, when an oil related problem is sensed a light is illuminated on the car's dash (usually in red) for driver note. The "idiot" factor comes to play in such a case where the manufacturer of the car decided that most drivers are either too idiotic to be able to read a full oil pressure gage, or they were simply too cheap to include such an instrument. Either case constitutes idiocy, at least from many auto professional's standpoint, as an "idiot light" will only come on AFTER a problem has occurred, with no advanced warning. An oil pressure gauge, on the other hand, allows the driver to see oil conditions at all times, thus allowing for the chance to note problems before they become critical-- i.e. The antithesis of idiocy.