What’s going on when the car heater fails?

Car Covered in Snow


Could the cold air coming out of my car’s heater indicate a serious problem?


While many different malfunctions can cause a heater to blow cold air, the most common one is low coolant. Here’s what you need to consider:

  •  If your vehicle is not equipped with a low-coolant warning light, the cold temperature from your heater will likely be the first symptom you receive.
  • Chances are, you have either developed a leak or your engine is consuming coolant.
  • The next likely symptom of a low-coolant problem is an overheated engine.

For many of these issues, you don’t want to delay the repair. If your car overheats, it can cause catastrophic damage to your engine and other systems under the hood, likely costing you a bundle.

Bottom line:

If a mechanic indicates that the heater problem is relatively isolated and won’t lead to catastrophic damage, take your time getting it fixed … as long as you can stand the cold!