Open the hood and grasp both of the hoses going through the bulkhead to the heater core with the engine running and at operating temperature. They should be hot, almost too hot to hold. If not, you may have a thermostat issue, or a temperature control valve issue.
With the engine running and radio off, move the temperature control from hot to cold and listen for blend doors opening and closing.
Tuesday, January 17th, 2012 AT 3:45 AM