The purpose for the Toyota parking lights and turn signals is more than just for aesthetics. These are considered safety devices so other drivers will not only see your vehicle but be aware if you decide to change lanes when in traffic. Unless your Toyota is in an accident or is vandalized, the parking lights and turn signal lenses should last the lifetime of your vehicle. The part that will wear out in time will be the lighting component or bulbs in the parking lights and turn signals. If you do need to replace either the parking lights or turn signal lenses or housing units, the old one should be pulled from the body of the Toyota first. This is the only way for the owner to know for sure just what is damaged and in need of being replaced. This way a broken hold down where a screw is fitted into the housing unit can be noticed if it has a crack in it. The last thing a Toyota owners needs is for the parking light or turn signal assemblies to have a crack in them that will permit moisture to enter the unit shorting out the bulb. Once the correct part or parts of the Toyota parking lights or turn signal assemblies is identified and purchased they can be placed back on the vehicle with only a screwdriver. This way the safety of the vehicle and the passengers riding in the vehicle will be back to its highest obtainable level once again. This is not a component on your vehicle that will improve its performance, but in most states, they are required to be properly functioning by law.