When I turn on the fan for the AC or Heater it doesn't come on until I turn it to the high setting. On the first three speeds there's nothing at all. At the fourth it comes on at full fourth setting speed. I tried turning on the AC. I pushed the button for the AC with it on high speed, and the AC came on. But then I turned it to a lower setting the light that says the AC is on went off. Any ideas what the problem could be?

 

I had the same symptoms on another dodge product and it was the blower motor resistor pack. I think ac shuts off if the fan is not on.




RESISTOR-BLOWER MOTOR
DESCRIPTION
The blower motor resistor is mounted to the HVAC air
inlet housing, directly behind the glove box. The
blower motor resistor consists of a molded plastic
mounting plate (1) with an integral wire connector
receptacle (2). Concealed behind the mounting plate
are coiled resistor wires contained within a ceramic
heat sink (3). The blower motor resistor is accessed
for service by removing the glove box from the instrument
panel.
The blower motor resistor is accessed for service by
removing the glove box from the instrument panel.
OPERATION
The blower motor resistor is connected to the vehicle electrical system through a dedicated wire lead and connector
of the HVAC wire harness. The blower motor resistor has multiple resistor wires, each of which will reduce the
current flow through the blower motor to change the blower motor speed.
The blower motor control in the MTC heating-A/C system directs the ground path for the blower motor through the
correct resistor wire to obtain the selected speed. With the blower motor control in the lowest speed position, the
ground path for the blower motor is applied through all of the resistor wires. Each higher speed selected with the
blower motor control applies the blower motor ground path through fewer of the resistor wires, increasing the blower
motor speed.
The blower motor resistor cannot be adjusted or repaired and, if faulty or damaged (such as a cracked ceramic heat
sink), it must be replaced.

 

I would also take a look at the switch.

You can find the whole panel pretty cheap if that happens to be the problem.

 

check the switch and the relays and fuses as well!

 

A friend of mine mentioned something about the switch being dirty.

One thing I forgot, I had noticed for several weeks when I would turn the fan on that it would make a noise. Sounded like a ball bearing going out in a computer fan. It would do it on the second speed setting. After about 15 seconds or so it would stop.

 

get the compressor checked!

 

If it was the compressor wouldn't the AC not come on at all? Or just do that when the AC is on?