The climate control system is a key part of that, keeping you cool on hot summer days and warming you up on chilly winter evenings -- but if neither the heat nor the A/C are working in your car, that tells us you've probably got a problem with your vehicle's blower fan.
Your AC's blower motor is responsible for moving air through your air conditioner to cool it and then pushing it back out into your home. Without this incredible component, your AC can't provide any cooling effect, no matter how much the compressor runs.
However, they can eventually burn out, so if your AC unit's blower motor is old, it might be time for a new one. One sign of a faulty blower motor is an air conditioner that still runs without blowing cool air. Remember: If the blower motor stops working, air is not moving through the system.
The blower motor lets you adjust the fan settings of your air conditioning (A/C) system. The blower motor turns the blower fan, which forces air through the heating, ventilation, and air conditioning (HVAC) system and out of the car's vents. Blower motors can operate at low, medium, medium-high, and high speeds.
The blower motor is responsible for circulating the air through the AC system. If the blower motor is not working, the air will not be circulated properly, which will cause warm air to be blown into your car.
Blower Motor Resistor Test
Typically, if the fan will work on some speeds but not on others, the resistor is suspect. Okay, let's say there's no melting going on, but your fan doesn't work on all speeds. Typically, if the fan will work on some speeds but not on others, the resistor is suspect.
The compressor is the core, primary part of every A/C system. They control temperature output with an electrically operated clutch. This clutch turns on and off whenever you change the temperature or if the HVAC module senses it has reached the desired temperature.
This could happen for a wide variety of reasons, such as a faulty wire, broken switch, or blown fuse. Another common reason is your compressor not turning on because it doesn't have enough refrigerant. Most compressors won't turn on if they go below a certain refrigerant level.
Your Compressor Might Be Broken, or Its Clutch Isn't Engaging. If refrigerant is the lifeblood of your A/C system, the compressor is the heart since its job is to circulate refrigerant through the system. Overheating, lack of lubrication, and low refrigerant levels are all common causes of compressor failure.
So what caused your air conditioner to stop working? Most likely, your AC system lost its charge of refrigerant. Or, due to an electrical fault, its compressor is not engaging when you turn on the system. Another possibility is that an internal obstruction is blocking the circulation of refrigerant.
Since it directly contributes to airflow, a bad blower motor resistor will affect your HVAC system's ability to both heat up AND cool down. If your fan seems to work properly, the speed settings function, and air is moving fine, but it's just not getting cold, then you may have a bad heater core.
The most common reason why your blower motor won't work on any speed is that you have a bad or blown a fuse. The most common reason why your blower motor won't work on any speed is that you have a bad or blown a fuse.
If the motor either burns out or short circuits, it will not function at all, which means you won't get any hot or cold air. In most cases, the mechanic servicing your vehicle will need to replace the blower motor entirely if you are to have restored operation in the system.
That being said, there are several fuses in your car's A/C, including ones to power fans and the ventilation system. In many modern cars, electricity even powers the A/C's compressor. So, if one of those fuses blows, you may experience other issues, like weak airflow, warm air, and poor ventilation.
The average cost for a Blower Motor Replacement is between $342 and $362. Labor costs are estimated between $68 and $86 while parts are priced between $274 and $276. This range does not include taxes and fees, and does not factor in your unique location. Related repairs may also be needed.
If your air handler is running but not blowing air, there are two likely scenarios: either a broken AC blower belt or an issue with the motor itself. If the air handler is humming or buzzing but not making the mechanical sounds of a motor running, you're most likely talking about an issue with the motor itself.
If you can hear your AC running, but the fan isn't kicking on you will want to try lowering the temperature on your thermostat a few degrees. If your fan is still suspiciously quiet, this can be an indication of an issues with the AC blower. The AC blower pushes the cold air out to the ductwork and through your house.
Flap Actuators. The air flows in an HVAC system through ducts or pipes; a flap is used to open or close, either fully or partially, certain portions of the duct in order to control which way the air goes. A flap actuator, also called a damper, is simply an electrical machine that moves the flap.
The A/C relay can usually be found in the vehicle's fuse box. The fuse box cover typically has a diagram illustrating the exact location of each relay. You can also look in the owner's manual. The vehicle's make and model will impact where you can find the A/C relay.
The AC system is responsible for circulating air through the system and into your home. Therefore, if you notice that there is low or no airflow from your vents, it's an indication there may be a problem with your blower motor that needs repair or replacement by a professional.
On some platforms, a faulty blower motor relay will cause the blower not to work at all, which means there will be no airflow from the A/C. On others, the blower won't work on “high blow” but all the other speeds will work. The blower motor relay fails because it regularly deals with high current loads.