Lexus GS300 1998 Owner's Manual page 442

ELECTRICAL COMPONENTS
64G020–1
" 1 Beam angle gauge (vertical movement)
2 Beam angle gauge (horizontal movement)
Before checking the headlight aim:
1. Be sure that the body around the headlight is not deformed.
2. Park the vehicle on a level spot.
3. The driver gets into the driver's seat and puts the vehicle
in a state readying for a driving (with a full tank).
4. Bounce the vehicle several times.
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