2007 Cadillac DTS Owner's Manual - Page 390

Headlamp aiming is done with the vehicle's low-beam headlamps. The high-beam headlamps will be correctly aimed if the low-beam headlamps are aimed properly. To adjust the vertical aim, do the following: 1. Open the hood. See Hood Release on page 355 for more information. 4. At the wall measure from the ground upward (A) to the recorded distance from Step 3 and mark it. 5. Draw or tape a horizontal line the width of the vehicle at the wall where it was marked in 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. 2. Find the center line running through the lens of the headlamp. 3. Measure the distance from the ground to the center line running through the lens of the headlamp. Record the distance. 390 6. Turn on the low-beam 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.