Cadillac 2004 Seville - Manual (Page 309)

Headlamp Aiming
Your vehicle has a visual optical headlamp aiming
system equipped with horizontal aim indicators. The aim
has been preset at the factory and should need no
further adjustment. This is true even though your
horizontal aim indicators may not fall exactly on the “0”
(zero) marks on their scales.
If your vehicle is damaged in an accident, the headlamp
aim may be affected. Aim adjustment to the low beam
may be necessary if it is difficult to see lane markers (for
horizontal aim), or if oncoming drivers flash their high
beams at you (for vertical aim). If you believe your
headlamps need to be re-aimed, we recommend that
you take your vehicle to your dealer for service.
However, it is possible for you to re-aim your headlamps
as described in the following procedure.
Notice: To make sure your headlamps are aimed
properly, read all the instructions before beginning.
Failure to follow these instructions could cause
damage to headlamp parts.
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