Lexus GS430 User Manual page 77

Automatic operation*
The wiper speed is determined by the vehicle speed and
the amount of raindrops and sunlight detected by the
automatic wiper control sensor.
Twist the automatic control adjuster in the "–" direction to
lower the sensitivity, and the "+" direction to boost the
sensitivity.
G12009
The sensor is on the inside of the windshield as shown above.
NOTE:
*Automatic operation can be changed to an intermittent
operation.
Ask your Lexus dealer for details.
With the engine 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.
D Turning the engine switch on with the wiper lever in the
"AUTO" position.
D Turning the engine 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 80_C or 176_F) or cold (at less than –10_C or 14_F).
When the engine switch is turned off with the wiper lever in the
"AUTO" position, and then the engine switch is turned on
again, the automatic operation may not work even if raindrops
are on the windshield.
In this case, move the lever to another position and return it to
the "AUTO" position again.
SWITCHES
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