I have an 89 300TE and the automatic heat control keeps turning the heat up to full blast no matter what the knob is set at. I cannot tell if the knob is broken or is the interior temp sensor isn't working. Does anyone have any thoughts?

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'05 Ford Escape 100,000 miles
'87 560SL 92000 miles
'89 300TE 199,000 miles
'02 Audi TT 100,000 miles
'00 Ford Excursion V-10 121000 miles
'92 Mercury Capri 100000 miles
'02 BMW 325XI 60000 miles
'92 230CE 160000
'87 BMW 535SI 160,000 miles
'93 Rinker Captiva 209
5 Kids
2 Dogs
1 Wife