2007 Hummer H3 Owner's Manual - Page 360

4. At the wall or other flat surface, measure from the ground upward the recorded distance from Step 2 and mark it. 5. Draw or tape a horizontal line the width of the vehicle at the wall or other flat surface where it was marked it Step 4. Notice: Do not cover a headlamp to improve beam cut-off when aiming. Covering a headlamp may cause excessive heat build-up which may cause damage to the headlamp. 6. Turn on the headlamps and place a piece of cardboard or equivalent in front of the headlamp not being aimed. This should allow only the beam of light from the headlamp being aimed to be seen on the flat surface. Passenger's Side Shown 7. Locate the vertical headlamp aiming screws, which are under the hood near each headlamp assembly. The adjustment screw can be turned with an E8 Torx® socket or T15 Torx® screwdriver. 360