My temperature knob on the a/c unit is stuck on the cold (blue) setting and won't move to the red (heat) section. Is this because it is simply stuck or is it because my 88'civic lx 4dr didn't come with a heater option. NOTE: This car spent 15 years in the Tropical Carribean Island of Puerto Rico before it was sent to Florida. What can I do to get my heater to work. I need HEAT!!! I'm freezin my ass off in the mornins.