Buick RIVIERA 1993 Manual page 103

Cleaning Photocells
Use a cotton swab and glass cleaner to clean the two
photocells that make the mirror work.
Outside Mirrors
The electric mirror control is on the driver's door.
Move the switch to the right (R) or left (L) to choose a
mirror. Press any of the four buttons to move the mirror
in the direction desired.
Adjust each mirror so you can just see the side of your
car and the area behind your car.
Heated Outside Rearview Mirror (Option)
The left outside mirror is heated when you turn on the
rear window defogger.
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