1999 Chevrolet Blazer Owner's Manual - Page 117

yellowblue Electrochromic Day/Night Inside Rearview Mirror (If Equipped) This mirror automatically changes to reduce glare from headlamps behind you. A photocell on the back of the mirror senses when it is becoming dark outside. Another photocell built into the mirror surface senses when headlamps are behind you. At night, when the glare is too high, the mirror will gradually darken to reduce glare (this change may take a few seconds). The mirror will return to its clear daytime state when the glare is reduced. The mirror will also return to its clear daytime state when the vehicle is put into REVERSE (R). Press the AUTO button at the base of the mirror to turn on the automatic feature. The button has an indicator light to show it is on. Press the OFF button to turn the automatic feature off. Time Delay The automatic mirror has a time delay feature which prevents unnecessary switching from the night back to the day position. This delay prevents rapid changing of the mirror as you drive under lights and through traffic. 2-53