See also:

If the light is blinking
If the light is blinking while driving, an engine misfire condition has been detected which may damage the emission control system. To prevent serious damage to the emission control system, y ...

Fuel
CAUTION Use of a fuel which is low in quality or use of an inappropriate fuel additive may cause engine damage. ...

Photosensors
The mirror has a photosensor attached on both the front and back sides. During nighttime driving, these sensors detect distracting glare from vehicle headlights behind you and automatically dim ...