My 1999 ford windstar se anti-theft light blinks all night and the next morning the battery is dead but the charging system and battery are fine what is causing the drain ALL SYSTEM ARE TURNED OFF?

The anti-theft light is NOT causing the battery to go dead. It sounds as though either somting is staying on or the body modules are not going into a "sleep mode" after the car has been turned off. Take the vehicle to your local Ford dealer as they will be the most qualified to diagnose the concern.

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