What usually causes the heating or air conditioning to stop working?
Although both heating and air conditioning are connected inside your car to some extent, they are actually separate systems. Your vehicle's heater uses heated engine coolant to heat the air that is blown into the passenger compartment while the air…
Although both heating and air conditioning are connected inside your car to some extent, they are actually separate systems. Your car's heater uses heated engine coolant to heat the air that is blown into the passenger compartment, while your air conditioner uses an engine-driven compressor in combination with high and low pressure lines, special refrigerant, and many other components.
Possible problems with the ventilation and air conditioning system of your car
The potential problems here vary, whether your heating has gone out or your vehicle's AC system has failed.
The most common reasons why the heating system does not work are:
- Low coolant level
- Air in the cooling system
- Faulty heater core
- Faulty (or defective) thermostat
Potential problems with the AC system are varied and include:
- Low refrigerant level (generally cool but not cold)
- Damaged compressor
- Damaged compressor clutch
- Damaged expansion valve
- Damaged evaporator
- Worn or stretched V-ribbed belt (required for compressor and clutch operation)
As you can see, both systems are very different. However, if you're having trouble with your HVAC controls, it's possible that the same problem will keep both the air conditioner and heater from working. For example, a faulty fan motor will not be able to force air into the passenger compartment. A faulty fan switch will make it impossible to adjust the fan speed. There are a number of other potential problems, ranging from a bad relay and a blown fuse to a short circuit in the wiring.
