Why is My Car Heater Not Working?  

 How to Fix a Not Working Car Heater

A car heating system may seem mystifying, with all its working parts integrated into such a much larger system. But, the heating system is actually relatively simple-seeming when compared to other subsystems of a vehicle. Still, the heater can develop a range of problems that can cause your car’s cabin not to heat properly. With the car heater not working, it can be too uncomfortable to use the car in cold weather, and a minor or major car heater repair may be needed. Below is a list of some of the most common causes of a car heater not working properly.

How Does a Car Heater Work?

A vehicle’s heating system consists of the heater core, fan, engine coolant system, and the heating and air conditioning setting controls in the dashboard. The process is pretty straightforward. When hot coolant enters the heater core, the heater fan, directed by the control settings you have set on the dashboard, blows the heat into the car’s cabin. This happens while the coolant is in a cooled state and is returning to the engine.

Why is My Car Heater Not Working?

If you have a problem with your car’s heating system, your auto repair technician will probably explore some of the most likely causes based on how the heating system is behaving. Some possible problems include:

Heater Fan Not Working

If the heater fan is broken or has a short, hot coolant (antifreeze) may be reaching the heater core, but heat may still not be blowing into the cabin of the vehicle.

Radiator Leaking

A radiator leak can stop the coolant from going to the car’s heater core to generate heat for the cabin of the car. This can damage your engine too, preventing sufficient engine cooling.

Antifreeze/Coolant is Low

This is one of the top two most common causes of lack of heat coming into the cabin of a vehicle from the heating system. It happens when the coolant level is low so the hot fluid cannot get to the heater core due to overworking the engine or not putting the correct amount of coolant in the radiator.

Thermostat Malfunctioning

When a broken or malfunctioning thermostat is the single most frequent cause of automobile heating systems suddenly failing to heat properly. A thermostat may become stuck closed or open, or develop other problems causing the heating and cooling system to stop producing.

Electrical System Issues

A problem with the car’s electrical system can cause many different types of problems in many areas of the vehicle’s overall operations, including the car heating and air conditioning system. If the heater is not blowing out any air at all or the temperature setting cannot be adjusted, then it may be due to something wrong in the electrical system.

Blower Motor Resistor not Working

If you are experiencing problems setting the fan speed in your car or air is not coming out of the vents when you set the heat/AC controls to blow air, the blower motor resistor may be broken.

Blown Fuse or Broken Wiring

The vehicle’s wiring may have a short or is possibly broken, preventing the necessary triggering of the heater from occurring when the driver sets the controls to turn on the heat.

Heat and AC Controls Not Working

The AC/Heater dials, knobs, buttons, or touchscreen commands may not be connecting with the heating system parts as necessary to trigger the heater to work properly.

Heater Core Clogged

A less common problem is having particles in the cooling system that have made their way into the heater core and caused a buildup until it is clogged. If a radiator is rusting inside or debris travels through the radiator and becomes caught in the heater core. This requires a large repair.

Why Choose Ace Auto for Your Car Heater Repair?

Ace Auto provides among the Salt Lake area’s best auto repair services, including heating and air conditioning services. All Ace mechanics are ASE Certified. All of our auto repair services are guaranteed.

If your heating system is not working in your car, call Ace Auto Repair at (801) 803-6016 for a free repair quote or to set an appointment for service.

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