Subaru 2001 Impreza Owner's Manual page 120

B Remote control mirror switch (if equipped)
The remote control mirrors operate only when the ignition switch is in
the "ON" or "ACC" position.
Direction control knob
Selection switch
HG0344
1. Press either end of the selection switch; "L" for the left and "R" for
the right.
2. Move the direction control knob in the direction you want to move
the mirror.
3. Return the selection switch to the neutral position to prevent
unintentional operation.
The mirrors can also be adjusted manually.
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