answersLogoWhite

0


Best Answer

Loss of vacuum supply to the HVAC controller. The vacuum supply comes from the pass side of the engine and goes through the firewall next to the AC lines. It is a small black line.

User Avatar

Wiki User

11y ago
This answer is:
User Avatar

Add your answer:

Earn +20 pts
Q: What is wrong if air blows out of the defrost vents only on 99 dodge ram?
Write your answer...
Submit
Still have questions?
magnify glass
imp
Related questions

Why does cold air only blows from defrost vents on a 1995 Chrysler concord?

Cold air from the defrost indicates that the air doors are in the wrong position. The doors are vacuum controlled in most vehicles. check the vacuum system for a leak.


Dodge ram 2003 ac wont blow thu vents whats wrong with it?

If it blows only out the defroster vents : then check for Vaccume leak Rick ASE L-1 Master TransMichigan.com


Why does heater defrost vent not open on a 1989 Sunbird and cold air blow from dash vents but no air blows from heater defrost vents and where are the enter and exit hoses for the heater coil?

I don't know why the vent would not open for the defrost, but it may be related to the fact that your heater core is blown. If your getting nothing but cold air out of the vents when the heat is on, your core is finished and if the core is finished then it is likely related to your vent not opening/switching. Something''s wrong with your heating either way.


What is wrong when the air conditioner on a 1989 Oldsmobile 98 regency blows out the top and not through the vents?

Could be a vacuum problem--either broken or disconnected hose or bad vacuum motor under dash or coming in through firewall Defrost is the default position for this system


Your heat is not blowing out of your floor vents but they blow out of the defrost and upper vents what could be wrong?

My guess is that you have a vacuum line that isn't connected or that has a hole. In the cars I've driven, the blower blows air into the heater box, where the heater core lives. Vacuum lines open and close flaps (or doors) on the heater box to direct the air where the control unit says it should go. These lines are usually rubber tubing, and the ends can dry out and crack, causing leaks. I have never worked on a dodge, but I've replaced miles of vacuum line on other cars.


The heat air and defrost do not work What is wrong?

The year, make and model info would help. Also need to know if the blower motor is working, just not getting any heat, or not changing function between defrost, dash or floor vents.


What is wrong when you cut the ac switch on and it only blows on the floor and the defrost but no air is circulating through the front vents no matter what setting you turn the switch to.00' cavalier?

Check for vacuum leak either under hood or under dash Check for bad vacuum actuator under dash Check for bad selector switch in dash


What is wrong with 03 trailblazer climate control won't switch from feet to head vents?

If the climate control on a 2003 Trailblazer will not switch from feet to head vents, try changing it to defroster then back to head. The mode button on the dual climate control model can only be switched from face/feet to feet and then to defrost. The feet and head vents worked at the same time.


Ac not blowing throw the vents in a 1996 Chevy lumina?

Check the floor heat vent and defrost to see if air comes from them. The vents will be vacuum controlled and a vacuum leak will make the vent doors divert air to the wrong place. Check the entire engine and climate control systems for a vacuum leak.


How can you change the air vent from your vent to defrost on a '77 Dodge Power Wagon with AC?

Make sure you have vacuum coming into the cab from the engine. There may be something wrong with the switches.


Why my ac air blows out the wrong vents on my 1997 Jeep Wrangler?

i had the same problem on my 99 wrangler, it was a leaking vacuum line. it was the one you see under the hood, against the firewall behind the battery.


My ac control will not switch from vents to defrosts etc it just blows out all the vents at once do you know what could be wrong I have already changes the control swtich panel and checked for a vac?

You either have a bad controller head or still have a vacuum leak or a cracked vacuum line and lastly problems with the a/c heater door operations..........