Your front blower motor has gone out. There is a front and a rear blower motor.
The air of your Chevy trailblazer 2004 blow out of the front vents when the air conditioner is on because the air condition is faulty and it needs repair.
thats because your blower went out
The front expansion valve is clogged.
Check your fuses.At first
Most likely the rear expansion tube or valve is defective.
probally closed or clogged
You need to check the vacuum lines for the a/c system for leaks, breaks and loose ones first.......
The moveable "baffle" inside the dashboard is not redirecting the air flow as it should. It's operated either by vacuum or an electric motor, in either case, repair is going to require the removal of the dashboard.
Faulty blend door control, clogged cab filter, weak HVAC blower, obstruction in the HVAC ducts.
The AC does not blow on the main front vents. Only rear and defrost.
The most likely cause would be a vacuum leak at the rear of the engine or a defective selector switch.
vacuum line to a vent door is not operating. Look under dash, have someone turn key on but not van motor listen for a sucking sound. That would be the hose either broken or unplugged or you'll end up going to a junk yard and get a new control module in the dash
The a/c - heater controller is out...........
Check all of your vacuum lines from the ac control panel and under your hood. You have lost vacuum somewhere witch controls your vents. There is one of them loose, disconnected or broken. Should be easy to trace. Good Luck!!
Under the hood in front of the transmission dip stick is a vacuum line. If it is disconnected or split it will make the air vents not work. If that's not it check your fuses.
It sounds like your vacuum controls are stuck on the defroster I had that happen and I sprayed a lubricant into the vacuum lines and it cleared up
Because most likely there is still coolant circulating through the system.
Air flow is controlled by plastic doors which are controlled by vacume motors. Could be they're stuck, or a vacume leak.
Check for a vacuum leak either under the hood or under the dashCheck the operation of the vacuum motors under the dashCheck the selector switch
why dont bottom vent doors not open on 2001 gmcsonoma
The flap that directs sir to the selected vents is jammed or broken...or the switch that controls it is.
An air conditioner evaporator is the part of the a/c system that the heat in your car transfers to causing cool air to blow from your vents. The blower is in front of it and it sucks air from the inside of your car and across the evaporator then blows out your vents.
Either the a/c system is low on freon or the evaporator has an internal restriction....
The blend door actuator may not be working.