Air Always On

chrysler
fans
airconditioning

#1

I have an 03 Chrysler Town & Country that runs with the A/C fans at 50% speed no matter what. I turn the A/C off and the fans will still run at 50% speed. With the A/C on I can increase the speed of the fans up 100% but never below 50% no matter what I try. The only time the fans are off is when the engine is off. Does anyone know what would cause this?


#2

Still looking for help!!!


#3

[b]One thing that can cause this problem is a defective ventilation control module. This is a small processor that controls all the functions of the vent system.

Unfortunately, the only way to have this system tested for proper function is to take it to the dealer.

Tester[/b]


#4

When you say A/C fans I am guessing you are talking about the cooling fan, the one(s) located right behind the radiator. If so, your problem may be unrelated to the A/C operation. It may be caused by any of the components of normal cooling operations.

These components include primarily one or more coolant temperature sensors and one or more fan relays. In rare instances the car’s computer may be defective.

You need to have your car’s electrical components checked out by someone who is familiar with such types of troubleshooting. There is no urgency.


#5

If you are talking about the fans that blow the air through the air conditioning vents in the car, it may be that this is the way it is supposed to be. Has this always been the case on this Town and Country? Some cars maintain some air flow through the vents at all times. I guess it is to keep the passengers and drivers from being asphixiated.


#6

I assume your are talking about the blower motor since you say you can control it somewhat at least.

There is a solid state speed control is between the control module and the blower motor. I have see a unit short and make the blower run at full speed before but haven’t heard of it failing and run the motor at half speed. It may be that there is a problem with the control module like a previous poster suggested or, it could be the speed control unit has failed but is still allowing some current through it. I would check the voltage on the control lead on the speed control module to see if the control unit is turning the speed control on partially. I don’t know what the normal OFF voltage is on the speed module but suspect it may be less than 0.4 volts. You may be able to check it also by removing the control lead to the module to see if that turns the fan off. If it does then the control module would seem to be the problem.

The speed control module can be found by just following the wires back from the blower motr. They will tie to the speed control module.

There is a diagnostic mode you can put the controller in to check things but without my manual I don’t know how to do that.