Recently, after a dealer oil change, the heater failed; only blowing cold air. After some digging around, I discovered that the driver side heat was non-functional, while the passenger side heat would work. (Most times I have the defrost function in place, so it was difficult to notice). Observations: 1) no clicking sounds. 2) coolant levels normative. 3) both hoses going to and from heating core are warm/hot after car has been running. 3) no leaks noted below the vehicle.

When I adjust the passenger temperature control from cold to hot or hot to cold, I hear (what I presume to be) the actuator adjusting cold to hot or vice versa. When I adjust the drivers side temperature control from hot to cold or cold to hot, there is no "noise" from the dash.

The preliminary steps and/or troubleshooting have not helped. My next step is attempting a "blend door reset." Should that not solve the problem, I will resort to replacing the driver side blend door actuator (I'm not sure if I will have a mechanic do this or attempt the service myself).

Am I missing something or am I on target with this? Thank you, in advance, for your input regarding this matter.

 

Sounds like you have a good plan of action.

 

Roger that! Thanks!