big body ac works but no heater

Are both heater hoses equally hot? If not the heater core is plugged up and needs to be backflushed. If not that then it's either the blend door, door actuator or switch

You gotta find that actuator an see if it's workin when u hit the switch for the heat. Not the blower speed switch. Google search is ur friend here

Try this http://www.cadillacforums.com/forum...including-1985/193333-94-deville-no-heat.html