1999 Crown Vic blowing cold air HELP!!

[michael99crownvic]

I have a 1999 Crown Vic with the automatic A/C heater control system. I'm having a problem with the heater..... It doesn't come on. Every time I set the temp for heat, on a cold day or when I need to defrost or defog my windsheild, it blows cold air. I have purchased the heater damper switch, but have no idea how it goes it or what it involves. Can someone let me know what I am in for???

[mikesea]

Did you get an answer yet.You probably have a problem at the blend door.Its a bear to get at.But my 97 had a problem with only HEAT.I removed the glove box door wire that stops the door from going all the way down.The remove the airbag for pass.side.be careful and disconnect the wire.You should then see down to the left the actuator for the blend door.I removed the screws and managed to manually move the blend door to the air only side.In S.florida that is all I wanted.I do understand the actual heat/air control on the dash often has issues and you may be lucky to replace it and problem solved.Another thing that worked ,I disconnected the positive cable for a few min. It supposedly puts the elec.system back to a default.The trick worked for a while.

[LastTudor]

Mike's probably right, but just for kicks, have you considered the thermostat? If it's stuck open, the engine will not get to the right operating temperature, and in some conditions will stay pretty cold.