While you can't adjust the focus of the headlights on your Volkswagen Passat, you can adjust the direction, or aim, of the headlights. Volkswagen recommends that you check the aim at least once every 12 months or any time you do front-end body work or change a headlamp bulb.
Make any necessary repairs to your car before you adjust the headlights.
Put your Volkswagen Passat in its normal driving condition. You want at least a half-full tank of gas and the proper air pressure in your tires. Leave any cargo that you normally carry in the trunk. Consider having a person of similar physique sit in the driver's seat while you make the adjustment.
Find a wall at least 6 feet high near a level area. Park your car next to another Volkswagen in front of wall. The headlights should face the wall at a distance of 25 feet. The car you use to compare the aim must have the correct aim, or your adjustment will not be correct.
Lift the hood and locate your adjustment screws. Most models have a horizontal adjustment screw on the exterior of the headlight housing and a vertical adjustment screw on the interior.
Check the low beam headlight aim and adjust before you switch to your high beam lights.
Twist the adjustment screws with a Torx bit.
Match the path for the headlights on your Volkswagen Passat with the car that has the correct aim. Stop adjusting when the path for your headlights matches the other car.
You may wear down your battery if you leave your lights on for an extended amount of time.
Most states have regulations mandating the allowed angle of your headlights.