I was hoping someone might be able to help me out. I have a 2004 Tahoe with Dual Zone climate control. My problem is that when I try to adjust the temperature set point using the knob, the digital readout goes down to about 60 degrees and will not adjust back up. When it originally started happening, it would initially start that way but after a minute or two I was able to slowly adjust the temperature back to the desired setting one degree at a time. Any insight as to what may be the problem?