Your air mix door is stuck, follow the cable from the temp control to the heater/ac unit and see if the flapper is moving, if not the door itself may be stuck or broken and you'll need to get in there and replace it.
If it's stuck in defrost your battery died and messed up the computer. Disconnect battery for 5 or more min. My 96 cooled and heated ok but was stuck in defrost
Yes, pull the A/C fuse or disconnect the compressor.
Check for a vacuum leak either under the hood or under the dashCheck the vacuum actuators under the dashCheck the selector control Defrost is the default for this system
Sounds like a stuck blend door.
does fan door motorized or on a vaccuum line when you switch from AC to defrost?
The AC on a 1998 Dodge Ram 1998 will only be blowing out the defrost vent if the air handler is not set properly. This can result from a piece of debris getting stuck or a faulty flap.
Yes, it will run when in defrost or mix.
Yes, the ac will run in the defrost position to dry the windshield.
the ac drain is stopped up locate under hood on passenger side on fire wall
Check for a vacuum leak either under hood or under dash Check the operation of the vacuum actuators under dash Check the operation of the selector switch Defrost is the default settting for this system
If it has AC assist and the compressor is shot, cut the belt or disconnect the defrost from the compressor.
the problem is when the baffles move from heat to ac and vent to defrost they either get stuck or the controllerr is bo. this system is built to fail safe in the defrost mode. Thus ac comes from Defrost vents. Apparently it is wide spred with Ford and Chev. As it is in my 2001 Ford F-350, My opinion To much Matel Toy company plastic and cheep parts we pay considerable money for from the dealers. 1) check your controller at the dash probably vacume 2) check the acutator at the butterfly flapper. Some vehicles are easier than others.....
If it's stuck in defrost your battery died and messed up the computer. Disconnect battery for 5 or more min. It worked on my 96
No. The ac and heater fan only has one resistor. The control switch is also failure prone on that vehicle.
Did you happen to move it to Defrost when you turned it off? The ac compressor also runs in the defrost cycle to keep the seals lubricated during the winter months when the ac is not used.
DO NOT FEAR THIS !!! The ac comes on with the defrost: because do you ever use your ac in the winter? me neither. Manufactures have made the ac come on with the defrost to prevent the ac compressor from seizing up. Since we never use them in winter, at least in cold climates. Cheers and drive on.
you have to trick the ac computer by shuting it off then restarting it...
You have vacuum line leaks somewhere.
Broken fins in the fan or a bad compressor. Or leaves and sticks stuck touching your fan for the ac side (assuming you have a separate fan for ac which you might not).
No, especially since the AC is used when you defrost the windows.
The ac system also removes humidity which helps clear the window faster.
It sounds like your air flow diverter is stuck on defrost. Basically it is a little door that diverts the air fom vent to defrost to feet. It could be either the heater control valve, or te temperature selecter cable is broke.
There is no A/C defrost relay. The defrost mode of the heating and air coditioning is a default mode whenever the system is not operating as it should. It automatically goes to defrost mode when the system is not operating as it should.