2003 GMC Sonoma Owner's Manual - Page 112

Mirrors Manual Rearview Mirror Pull the tab under the mirror toward you to reduce the glare from headlamps behind you after dark. Push the tab away from you for normal daytime operation. AUTO: This button is located at the base of the mirror. Use it to turn on the automatic feature. The button has an indicator light to show it is on. OFF: Press this 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. Automatic Dimming Rearview Mirror If your vehicle has this feature, the 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 vehicle is put into REVERSE (R) or when the glare is reduced. Cleaning the Photocells Use a cotton swab and glass cleaner to clean the photocells and mirror face when necessary. Cleaning the Mirror When cleaning the mirror, use a paper towel or similar material dampened with glass cleaner. Do not spray glass cleaner directly on the mirror as that may cause the liquid cleaner to enter the mirror housing. 2-37