2008 Crown Victoria Police Interceptor just blows air... not hot, not cold, just air

When I turn on my air conditioner it just blows air, not cold air just air. If I turn it to heat it also just blows air, not warm air, just air. The fan settings all work fine but the air coming out never changes temperature. By the way, If I bypass the compressor clutch relay with a paper clip, the AC will kick in. I refilled the coolant in the AC system too but it won’t engage without bypassing the relay. Plus, the heater is not “kicking in” either. I did recently install a new wiper motor but I am not sure if that may have contributed to the air issue that is happening now.

Does this have an electronic climate control unit, or ‘standard’ controls?

I believe they have a BCM that controls all the HYVAC functions electronically…Try this. Place the heater / AC controls in the “off” position. Disconnect the battery for a few minutes. Reconnect and see if control function is restored. You can take your problem to www.crownvicnet.net where the true believers gather…

@ oblivion standard. it just has 3 knobs- fan speed, temp., and function. Caddyman, I will give the battery thing a try tomorrow morning. Thank you!

One thing, that whole dashboard comes apart without much fuss…That temperature control knob is regulating the “blend door” on the heater plenum (air box) Whether it works directly or through a master BCM, (body control module) I am not sure. Maybe you can remove the glove box and peer into the heater controls that way…

Don’t know if that is vacuum controlled or not but if you were messing under the hood, I’d make sure the vacuum line going to the HVAC controller is intact. Otherwise nothing will work. Doesn’t explain the compressor though so don’t spend much time on it.

I forgot to mention that I also replaced the MFS prior to the wiper motor. Is there something under the dash I could have knocked lose while doing the MFS?

drop the glove box and see if the blend door actuator moves when going from hot to cold,it’s on top to your left,black if you have auto and white if you don’t,if it’s not moving the door it’s probably no good,tap on it might help temporarly