From the time I bought from the dealer. It only works when I go up to MAX HOT position. Just cold or not that cold is all the variation I have!
I never noticed this as I don't really need heat (California) but some of the passengers have complained about this and so I tested it - unfortunately after the warranty expired.
Could this be just because of a servo failure?
Any ideas, appreciated, on how to fix this now at a reasonable cost. This is actually a manufacturing issue but dealer wants money now as it is out of warranty.
Thanks

 

Welcome to CL. Try purging air in your heater core sometimes that's the cause of the lack of heat. Let me see if I can remember, put your car on an incline with the hood higher, open your radiator cap, run the car and set your heat to max. Let it run for a while. Watch If you can see airs bubbles come out of the radiator. It may solve your issue.

Try to read though posts here, lots of tips and tricks. Good luck.