To remove the minor mold from vynal siding, you need to first of all identify mold growth. You will then spray the affected area using a pressure washer or a garden hose that has with a high-pressure spray nozzle. Prepare 3/4 cup of household bleach and a gallon of water in a bucket to use over the affected area. Check out http://www.ehow.com/how_4464263_remove-mold-from-vinyl-siding.html for more information.
There are several good brands of mildew removal sprays such as Tilex. They're usually used in bathrooms but they're safe on vinyl siding. You should hose off the areas you clean to make sure there's no chemical residue left after cleaning.
Definitely go with ConMah's answer to take care of this problem , DANGER ! . . . NEVER run chlorine bleach through any pressure washer , Many of the pump's parts are aluminum which will seriously corrode these parts which can cause the pump to rupture violently and cause serious injury to yourself and persons standing nearby including injection injury , If an injection injury occurs , It will appear as a cut and if this happens , Immediate medical aid at the emergency room MUST BE OBTAINED When using chlorine bleach , Wear your P.P.E. ( Personal protective equipment ) , Especially gloves and full safety goggles to keep bleach from getting into your eyes and on your skin