Make sure coolant is full, make sure engine is warming up to operating temp, make sure coolant is flowing through the heater core. If all is good, check the blend air door.
Dec 24, 2012 at 4:39 AM
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.