In the last few days I have just noticed that when I start up my car the HVAC defrost button is lit up. Up till now the button that was pressed when I turned my car off (top vent) would remain lit when I restarted my car. Now no matter what button I have selected when I turn my car off, it always returns to defrost when I restart. FWIW, fan is set to off and temp control is on cold. After starting the car I can switch buttons to whatever and everything works fine. Am I missing something here??