Aiming; Low-Beam Headlight Pattern Alignment - Chevrolet Trailblazer Service Manual

Aiming

When adjusted properly, the lights should not glare in oncoming traffic's windshields, nor
should they illuminate the passenger compartment of vehicles driving in front of you.
CAUTION
When headlights are replaced or any time front-end work is performed on the vehicle, the
headlights should be aimed using the proper equipment. Headlights not properly aimed
can make it virtually impossible to see and may blind other drivers on the road, causing
injury or death.
1. Park the vehicle on a level-surface, with the fuel tank about 1/2 full and with the
vehicle empty of all extra cargo (unless normally carried)
The vehicle should be facing a wall that is no less than six feet (1.8m) high
and 12 feet (3.7m) wide
The front of the vehicle should be about 25 feet from the wall
If aiming is to be performed outdoors, wait until dusk to properly see the
headlight beams on the wall
If done in a garage, darken the area around the wall as much as possible
by closing shades or hanging cloth over windows
2. Turn the headlights ON.
3. Mark the wall at the center of each light's low beam.
4. Turn on the high beams and mark the center of each headlight's high beam.
5. A short length of masking tape that is visible from the front of the vehicle may be
used.
NOTE: Although marking all four positions is advisable, marking one position from
each light should be sufficient.

Low-beam headlight pattern alignment