DESCRIPTION
Note. References to "new style" refer to Sierra, Silverado, Suburban, Tahoe, Yukon and Yukon XL models equipped with 4.8L, 5.3L and 6.0L engines. References to "old style" refer to Escalade, Pickup, Tahoe and Yukon models equipped with 5.7L, 6.5L and 7.4L engines.
Electrochromatic day/night rearview mirror automatically changes reflectance to reduce glare from headlights. At night, as glare of headlights from behind increases, mirror will gradually become darker to absorb glare. During daylight or when gearshift lever is in Reverse, mirror will be clear and fully reflective. On some models, driver's side outside mirror will also be an electrochromatic day/night mirror that is controlled by inside mirror. On some models, inside rearview mirrors also include a compass.
OPERATION
Day/night mirror(s) use a thin layer of electrochromatic material between 2 plates of conductive glass. Two photocell sensors signal levels of light to a logic circuit. A forward-facing photocell sensor measures ambient light levels. A rear-facing photocell sensor measures glare from approaching vehicle headlights. When logic circuit senses more light from the headlight sensor than the ambient light sensor, the electrochromatic drive circuit applies voltage to mirror(s). Approximately 1.15 volts is applied to mirror(s) when a large amount of glare is present, causing mirror(s) to darken. Voltage will be reduced to 0.01 volt when both photocells indicate the same light level.
When gearshift lever is shifted into Reverse, battery voltage is applied to mirror reset terminal. Mirror will gradually change to a clear state for better vision when backing up.