Lexus 2003 LS Owner's Manual page 44

SWITCHES
Raindrop detection type
12L074c

1 Automatic control adjuster
To turn the wipers on, move the lever down until you reach
the desired speed setting.
The ignition switch must be in the "ON" position.
There are 3 settings:
"AUTO" position: Automatic operation
The wiper speed is determined by the amount of raindrops and
sunlight detected by the windshield sensor (shown in the
illustration), and the vehicle speed.
"LO" position: Low speed operation
"HI" position: High speed operation
Twist the automatic control adjuster in the "–" direction to
lower the sensitivity, and the "+" direction to boost the
sensitivity.
30
With the ignition switch turned off, if the windshield sensor is
touched by reason of cleaning the windshield or for any other
reason, either of the following operations may cause automatic
wiper activation.
A Turning the ignition switch on with the wiper lever in the
"AUTO" position.
A Turning the ignition switch on and move the wiper lever
down in the "AUTO" position.
Even with the wiper lever in the "AUTO" position, the system
will switch to intermittent operations if the system malfunctions.
The system will turn off if the windshield gets extremely hot (at
more than 80BC or 176BF) or cold (at less than –10BC or 14BF).
2 Washer on
Be careful not to get your fingers caught between the
wipers and windshield.
When the wiper lever is in the "AUTO" position with the
ignition
automatically in the following cases:
A If you touch the upper center of the windshield
A If you wipe the upper center of the windshield
A If the windshield vibrates.
A If you touch the sensor.
CAUTION
switch on, the wipers
adjacent to the sensor.
(adjacent to which the sensor is located) with a towel.
could operate