Many premium cars feature GPS units that are built into the dash. These systems use road maps stored on either SD cards or DVD/CDs. If your car uses a DVD to feed information to the GPS unit, then the DVD can be removed by pressing on the "Open" button, usually located on or near the dash. If you are having problems with the map disc, then there are several ways to potentially repair the DVD, meaning you won't have to go and buy a new DVD to replace it.
Switch on the car's interior lights and hold up the underside of the DVD to the light. Search for grease marks that you may have inadvertently caused when handling the DVD for the first time -- or that a child may have caused when playing with the in-dash unit. Gently rub away the grease marks from the inside to the outer edge of the DVD using lint-free optical cloth. If this does not work, go to Step 2.
Hold the cleaned DVD under the in-car light again. Locate any scratches; these can interfere with the ability of your car's GPS unit to read the disc correctly. Take a cotton swab and apply a small amount of toothpaste to any light scratch you locate. Gently rub in the toothpaste and once done, use a moist cloth to wipe away any excess toothpaste. Work your way from the center of the DVD to the outer edge when cleaning. Ensure that the DVD is dry before sliding it back into the GPS system. If the scratch is deeper, then try Step 3.
Take a piece of soft paper toweling and apply a small amount of metal polish such as Brasso. Apply the polish to the DVD, working your way from the inside edge of the DVD to the outer rim. Remove any remaining polish by rinsing the DVD with water. Make sure that the DVD is dry before reinserting it into the GPS unit.
