2003 Cadillac Seville Owner's Manual - Page 299

Headlamp Aiming / \I 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 i possible for you to re-aim your headlamps s 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. The vehicle should be properly prepared as follows: 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. The vehicle should be placed so the headlamps are 25 ft. (7.6 m) from a light colored wall or other flat surface. 0 The vehicle must have all four tires on a perfectly level surface which is level all the way to the wall or other flat surface. 5-50