Car heater does not blow heat through vents or defroster onl cold air.
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2003 Nissan Altima Question: Heater does not work
Answer #1candaautomotive from C and A Automotive, January 07, 2011, 12:27Journeyman
Possible blend door actuator or thermostat?
Answer #2Tyreguy January 07, 2011, 12:34Master
Check the antifreeze level first in the radiator and the recovery tank (when the engine is cold). If its low, add as neccessary and get to a service facility to check for leaks. If the antifreeze is full (at proper levels) it will still need to go to a service facility and check other cooling system problems that may be causing your no heat issue.