Climate control system acting funny - Impala

nmwanta901

I've been using the heat for the past couple days being cold this year for the first time in my 2011 Chevy Impala LT (w/ heated seats), and there's a couple weird things with it. First, it doesn't seem to get as hot as I would have thought, or as my other past vehicles have. Second, the fan doesn't seem to run the fastest on all of the settings. There is still a progression from low-high, so it's not like its one speed only, but it seems to be just running slower on all settings. Lastly, when you switch from, for example, face vents to defrost, the blower motor shuts off, and then it takes forever for it to switch between those vent modes, and then the motor seems to turn back on. At first I thought it might be the heater core, but that wouldn't explain the other stuff. Same for the blower motor resistor, but it doesn't explain the less heat output. Would it possibly be the climate control module under the radio that is going bad?