Audi electronic check
Top-of-the-range Audis have an electronic check system that automatically monitors various systems.
When the check system detects a serious fault, such as loss of engine oil pressure, it displays the oil-pressure symbol on a red background and sounds warning chimes to alert the driver to the danger.
A more minor fault, such as low washer fluid, is displayed on a yellow background to show that it is less serious.
The driver can run the auto-check system by pressing the check button. If all is well, the system lights up 'OK'.