Driving home on the turnpike a couple of days ago, the environmental system was only putting out heat when it should have been cooling. Cranking the setpoint down to "Lo" resulted in lots of fan and no cooling - 135° air coming out of the vents. Anyone else had this happen? The AC clutch is engaging. The system apparently just isn't moving the right doors to mix the air.

 

Sounds like the hot/cold air blend door motor could be stuck. Each side has a motor unit. 79150-TLA-A51, 79150-TAA-J41.

 

Thanks for the information. That's pretty helpful! After driving 150 miles and 2 additional days around town with full heat, you might know the problem wasn't present at the dealer. I just got the car back, and it's all working fine. They've never seen this issue before. They even called the factory rep. It was new to him, also. Just hoping it doesn't manifest itself again next winter after a cold snap.