heater not working on 2005 Nissan Altima

the heater only works while the car is in motion, but as soon as I stop at a red light or whatever, it starts blowing cold air. ?????

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2 answers
There is a technical service bulletin (TSB) from Nissan regarding this issue. It involves a thorough diagnostic procedure that needs to be followed to help determine the cause of this issue. Here is some of the info below. I would take this to the dealer or a good shop that has access to this TSB and have them check out your car.
Bulletin# NTB02-047c Reference: Date: March 7, 2007
Air from the heater on an Applied Vehicle:
• Takes a long time to warm up after an engine cold start, or
• Output air cools down and is not warm enough while the engine is at idle, or
• Output air is not warm enough at any engine speed
Refer to the DIAGNOSTIC FLOWCHART to determine the course of repair. That course may include all or some of the following:
• Coolant Mixture Inspection procedure
• Coolant Mixture Correction procedure
• Cooling System Bleed Procedure
i had the same problem and it was easily fixed. it seems that the antifreeze/ water ratio must be what the car recommends. I had to much anti freeze. my uncle took some out put some water and the heater started working properly.