We have three 2003 trucks at work. One is a hemi and the other two are diesel. All are 4X4. All are having the same problem.

You can turn on the air or just the defrosters and you can hear lots of air moving but it doesn't seem to go anywhere. You can put you hand over any air outlet and not really feel any air movement but the blower motor is on full speed.

By looking through the threads it appears to me that there is a problem with the blend doors not working.

On my truck you can sometimes hear a pop sound and then the air will move properly.

Does the dash need to be taken apart to get at the HVAC to service it? How common is this problem? I checked on TSB's and didn't see one but my truck is out of warrenty anyway. Is this something you can fix yourself or will it need to go to the dealer.

Just looking for some input on this. Sometimes this can be a real problem when defrosters don't work.

 

Mine is in the shop once again as I post this reply, for the same problem. It sounds to me that the recirculation door is not operating. Turn the AC on and switch back and forth between fresh and recirculation. You should hear and feel increased air flow when swithed to the recirculation setting. If not, either the recirculation door is broken or the actuator motor is inoperable. If you are having trouble changing output positions, then the blend door is broken. All of the above conditions require the removal of the dash to repair the problem. In turn this gives the tech a license to kill my truck. It has been damaged in some way every time the dash has been removed. Welcome to the DC HVAC problem club. I have lost track of how many times my truck has been in the shop for HVAC problems. I would have to check my records. I will say it is getting old. DC junk! Plain and simple.

 

If your system is similar to mine, it sounds like you've got a vacuum hose off.

Mine was on the firewall drivers side. It was about 1/4" dia. and was at a Y.

When mine failed the system defaulted to defrost. It sounds like yours can't get there. Might not be the same thing.


Dave

 

The 3rd Gen trucks dont have vacume.

 

First time I heard that. I will keep that in mind, when I get another truck.

Dave