Tauruses are known for transmission issues. This code and symptom can mean many different things from a transmission range sensor, to solenoid wiring issues and more. Your best bet is to pay an experienced technician to properly diagnose the problem.
RepairPal Certified shops can diagnose and repair your 2004 Ford Taurus. They provide transparent pricing with a minimum 12-month or 12,000-mile warranty on repairs and services.