2003 Cadillac DeVille Owner's Manual - Page 320

you take your vehicle to your dealer for service. However, it is possible for you to re-aim your headlamps as described in the foiiowing 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: The vehicle should be placed so the headlamps are 25 ft, (7.6 m) from a light colored wall or other flat surface. 0 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 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. The vehicle should be placed so it is perpendicular to the wall or other flat surface. The vehicle should not have any snow, ice or mud attached to It. The vehicle should be fully assembled and all other work stopped while headlamp aiming is being done. The vehicle should be normally loaded with a full tank of fuel and one person or 160 Ibs. (75 kg) on the driver's seat. Tires should be properly inflated. 5-49