It’s one of the most dreaded morning scenarios there is: you walk outside to your warmed-up car, turn the heater to high, and cold air comes out. If you’ve ever dealt with this situation in the middle of winter, you know how frustrating it can be. So, before the chillier temps are upon us, it’s best to start preparing. At AA Auto Tech, we know a fully functional heater is an absolute necessity over the coming months. Today, we’re here to discuss four reasons why your vehicle’s heater may be malfunctioning, and what you can do to fix the problem.


You Might Have a Bad Thermostat

Normally, when your vehicle’s engine is warm, the thermostat opens, allowing coolant to flow through the engine. Coolant regulates the temperature of the engine by transferring heat buildup either toward the exhaust, or the heater core. When your thermostat is broken or stuck, however, it does not open and close as intended.


If the thermostat remains open, coolant continually flows through the engine, causing it to run cold. If it remains closed, heat builds up within the engine but does not have anywhere to go. Either one of these scenarios can result in cold air blowing from your vents. If your coolant levels are normal, but your vents blow cold air, have your thermostat evaluated by a qualified mechanic.


Malfunctioning Heater Core

Your vehicle’s heater core functions as a kind of mini radiator, transferring and dispersing heat away from the rest of the cooling system. When you turn on your cabin heat, your blower pushes this warm air through your vehicle’s vents. But, if there’s a problem within the heater core, this heat transfer does not occur. Signs that you may be dealing with a bad heater core include:


●        Overheating engine

●        Window condensation

●        A sweet, fruity smell inside the vehicle cabin

●        Excessive coolant usage

●        A cold cabin, but a hot engine


If the heater core has a leak, your vehicle will require extra coolant just to keep the motor at normal operating temperature. You may also smell a sickly-sweet odor if coolant leaks and then evaporates into steam as it meets the air within your cabin. Regardless of what may be causing the core to malfunction, it is imperative that you have it examined by a trained technician. Your motor is designed to operate a specific temperature; fluctuations outside this temperature range can result in serious, possibly irreparable engine damage.


Low Coolant Levels

As we’ve discussed, coolant functions to cool your engine. On the flip side, it also works to heat your car. To maintain a normal engine operating temperature, coolant flows through the engine and disperses heat either toward the heater core or out through the exhaust. When there is not enough coolant, however, warm coolant won’t travel to the heater core, and consequently, you won’t feel warm air when your heater is on. If your vehicle has had plenty of time to warm up, but still blows cold air, the first thing you should do is check your coolant level.


Bad Blower Fan

If you have a bad blower fan, warm air cannot circulate into your vehicle. The blower fan is designed to push warm air from the heater core through your vehicle’s vents, and if it malfunctions, you won’t feel airflow when you turn your heater on. The issue could be the result of faulty wiring or a blown fuse, both of which are easily repaired by a certified auto mechanic.


Expert Heating and Air Conditioning System Repair

At AA Auto Tech, our ACE-certified mechanics are dedicated to providing the best possible care for your vehicle. We know how brutal the Hastings winters can be, and that’s why we’re here to help you prepare. If you’re getting your vehicle ready for the cold weather and find that your heater isn’t quite up to par, our team would be happy to serve you. Whether you need routine maintenance services or a more extensive repair, we offer the expertise you need and service you can trust. For any questions, or to schedule service on your vehicle, don’t hesitate to contact our knowledgeable team at 651-437-2218.