Common Car Heating System Issues

With freezing temperatures approaching, having a fully functioning heating system in your vehicle is vital for a comfortable and safe driving experience this winter/fall. Your car’s heating system plays a crucial role in keeping you warm during the winter months, defrosting your windshield, and ensuring your engine is running as smoothly as possible. In this article, we’ll explore the common problems of a car heating system and the components that make up the system.

Common Issues With Car Heating Systems

Like any system in a vehicle, there will be problems. Here are the most common issues with cars. By understanding the common issues and proper maintenance practices, you can ensure a warm and satisfied ride even on the coldest days. If you encounter persistent heating issues, it is best to consult a professional auto mechanic to diagnose and repair the problem effectively.

The system control panel of a car

Common Heating System Issues:

  • Low Coolant Level
  • Failed Heater Control Valve
  • Clogged Cabin Air Filter
  • The Heater Fan/Fan Resistor
  • Faulty Climate Control Panel
  • The Heater Core is Leaking or Blocked
  • Faulty Thermostat

Low Coolant Level

Low coolant in your vehicle is one of the most common reasons why your heater isn’t working properly. The coolant in your vehicle should never fluctuate; if there’s a leak somewhere or a blown head gasket, you could be consuming coolant. This causes the heater core to not get the proper amount of hot antifreeze for heat enhancement, which makes your vehicle nice and warm. This is commonly caused by a cracked coolant tank, a damaged coolant hose, a leaking water pump, or a faulty head gasket. Other cooling system parts can leak, so it’s important you check them regularly.

Failed Heater Control Valve

The heater control valve is used to divert or stop hot antifreeze from being routed into the heater core, which produces overall heat for the vehicle. When a heater control valve fails, one of two things is most likely to happen: it will either start leaking or it will seize in the closed position, causing your vehicle’s heater to blow cold air.

Clogged Cabin Air Filter

The cabin air filter is one of, if not the most important, components in your vehicle’s heating system. The primary function of the component is to prevent dust and other debris from entering the cabin; however, it does need to be replaced regularly to prevent reduced airflow.

The Heater Fan/Fan Resistor

Another common issue with blowing cold air is that the heater fan on most vehicles is relatively easy to replace, but some fans are harder to get to, commonly located inside the heater box. If there isn’t an issue with the wiring or the fuse, another culprit to look at is a blower motor resistor. This controls the various fan speeds, but it can sometimes completely fail. If you have a specific fan speed that is not working, then the resistor is almost always the culprit.

Car interior air conditioning control panel

Faulty Climate Control Panel

The climate control panel is used to control temperatures and settings of the heating system. Your climate control panel can have an internal failure, causing the switches that control the blower and blend doors to work or fail.

The Heater Core is Leaking or Blocked

Your vehicle’s heater core is the main source of heat inside your vehicle. It utilizes the hot antifreeze and turns it into heat. Sometimes the heater core can become blocked, due to old, forgotten antifreeze, and since the heater is only used for a couple of months of the year, this allows sediment and corrosion to settle in the core’s passages, creating restrictions and blockages. Without a proper flow of anti-freeze, no fresh, hot antifreeze can enter the core. A faulty heater core can also leak, which causes a major problem. It can fog up the windows with antifreeze mist, which is very dangerous. The vehicle will also have a sweet, antifreeze smell in the cabin when the heater is running.

Faulty Thermostat

A faulty thermostat within your vehicle can also be the main cause of your car’s heating system not functioning properly or not working at all. The thermostat is one of the most important components within your car, helping keep the engine’s temperature at a safe and functioning level, and directly affects the heating and cooling in a car. Most of the time, when replacing a thermostat, you’ll also need to change out the current coolant within the vehicle.

Maintenance Tips

Here are some maintenance tips to keep your car’s heating system.

  • Check Coolant Levels
  • Flush Heater Core
  • Inspect Thermostat
  • Replace Cabin Air Filter
  • Routine Inspections

Heating System Service In Naperville

Becker Service Center in Naperville, IL, can perform any of your heating system needs so you can continue to drive with comfort and peace of mind. Our ASE-certified technicians will inspect your heating system to pinpoint the source of the issue for top-tier diagnostics and potential repairs it with the highest quality of parts and service! Call or schedule online today to meet with our team of experts!