Lexus 2003 LS Owner's Manual page 141

When the outside air temperature is low, it may take a little
longer for the mirror to darken in response to the detection of
headlights.
CAUTION
Do not adjust the mirror while the vehicle is moving.
Doing so may cause the driver to mishandle the vehicle
and an accident may occur resulting in death or serious
injuries.
COMFORT ADJUSTMENT
16L608a
To ensure correct functioning of an anti–glare mirror
sensor located on the back side of the mirror, do not touch
or cover the sensor with your finger or a piece of cloth, etc.
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