I used to be able to set my a/c control to 60 and the fan motor would blow full speed regardless of the inside/outside temps. Now, this only works when the car is very hot inside. Once the car is cooled down, setting the a/c temp control to 60 does not cause the fan to run full speed. I'm thinking maybe a sensor has gone bad or the a/c control unit itself is bad. It's a minor thing but I know this unit is designed to run at full speed heat and/or cold if you set the thermostat to 60 or 90. BTW, the 90 setting is still working fine (full heat). Any ideas or similar experience?