[s-cars] Quick Heating question

[NDoshi at aol.com]

Last night, I noticed a symptom on the S6 - With the heat on, the temperature 
controls did not have any effect on regulating the temperature, It got really 
hot with air coming out of the dash vents even though they were not manually 
selected. The only way to get the temp to come down was to set the temp to low 
(lo) which seemed to work intermittently
Any ideas before I start ripping stuff out.
Nick