Chech heater core hoses .. if they are getting hot check blend door is opening correctly
Heater system is a blend-air type, consisting of a control panel, blower motor and plenum assembly. Blower motor is located in plenum assembly, under instrument panel. Plenum assembly contains heater core, floor/defrost door, panel/defrost door and electric motor actuated temperature blend door. See Fig. 1 .
Check for low coolant level. Check for pinched, damaged, collapsed, or improperly routed heater hoses. Ensure engine is not overheating. Check for plugged or partially plugged heater core.
TEMPERATURE CONTROL KNOB
Temperature control knob controls a blend door potentiometer which controls an electronic temperature blend door motor. Temperature blend door motor provides a variable number of temperature blend door positions. When temperature control knob is in COOL position, temperature blend door shuts off airflow to heater core. When knob is in WARM position, air is directed through heater core. When knob is in intermediate positions, heated air is blended with cooler incoming air to achieve desired temperature.
Monday, December 15th, 2008 AT 6:39 PM