Lexus GS430 User Manual page 617

G64027
Turn the bolt A in either direction using a Phillips−head
screwdriver.
ELECTRICAL COMPONENTS
64G084
" 1 Red line
2 Acceptable range
Horizontal movement gauge: The red line should not
deviate by more than 2 blue lines to either side of the gauge.
If the red line is out of the acceptable range of the beam angle
gauge, adjust it using bolt B.
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