Your mom has a 2001 Dodge Caravan and her ACheater when turned on is making a hissing noise and when turned on you can hear it heating or cooling from the outside Is this some kind of fluid problem or?
My Wife's 1998 Dodge Caravan's air conditioning system is making a "hissing" sound when it is turned on. It sounds like it is from the inside of the car. When I called a local dealer they suspect it may be the evaporator coil leaking. They gave an estimate of $800.00 plus but would try and determine if that was the problem. We may or may not try to have it fixed. If we do I will try and advise what happens.