What to Do When the Car Air Conditioning Isn't Heating?

[VanColeman]

It is recommended to check the heater core for any blockages. If found, replace the heater core. It is suggested to clean or replace it as necessary. It is advised to visit a 4S shop to replace the new component.

[DelRebecca]

My old Jetta had this issue last winter too - the AC was blowing cold air. First thing I checked was the coolant reservoir, and sure enough the level was below the minimum mark. When engine coolant temperature is insufficient, it can't properly heat the cabin - that's basic knowledge. You'd better check the inlet and outlet hoses of the heater core after warming up the car. If there's significant temperature difference between them, it indicates poor circulation. If the hoses feel soft, the thermostat might be stuck open - replacing it only costs about 100 yuan. By the way, never top up low coolant with plain water - the changed freezing point could crack the radiator. I once took the easy way out by adding tap water, and ended up with three cracks in the radiator come winter - 800 yuan repair bill that I still regret to this day.