Cadillac 2010 CTS Sport Sedan Owner's Manual page 335

To adjust the vertical aim:
1. Open the hood. See
for more information.
2. Locate the aim dot on the lens of
the low-beam headlamp.
3. Record the distance from the
ground to the aim dot on the
low-beam headlamp.
4. At a wall, measure from the
ground upward (A) to the
recorded distance from
Step 3 and mark it.
5. Draw or tape a horizontal line (B)
the width of the vehicle at the
wall where it was marked in
Step 4.