1999 Ford Windstar My Car Won't Start

Have the battery load tested if it won't hold 9.6 volts in 10secs its no good-if okay make sure its clean and properly tighened then try again don't work come on back-

Your possible problems are Ignition switch, park and neutral switch, starter relay and starter itself-

Sounds like your battery connections are dirty or loose. During electrical high demand times such as during cranking, bad battery connections can cause your symptom as you describe. However, your lights and accessories may magically reappear after you cycle the key from on to off to on again. Then when you turn the key to start the car, you hear a little click (or nothing at all) and all electrical stuff goes dead.

If this is the case, definitely check the battery terminal posts and connections.

Other variables: Try wiggling the gearshift lever and/or moving the gearshift to Neutral and try to start the engine in Neutral. There is a safety switch which prevents the starter from cranking the engine. If it is misaligned just a little, the engine will not crank. Moving the gearshift gives the switch a chance to land on it's happy spot where it allows the starter to energize.
Good luck.