In most cases, a blower motor resistor fails due to corrosion or overheating. Sometimes, the mechanical resistance to the motor rotation causes an excessive electric current that can overheat and prematurely damage the blower motor resistor.
How long should a blower motor resistor last?
The blower motor resistor is designed to last for the car's lifespan. In most cases, these resistors will wear out long before the car does. Usually, the wear that the blower motor resistor has is due to the constant use that it gets and the heat that it is exposed on a regular basis.
Why does my blower motor keep burning out?
Buildup of dust, dirt, or debris. Electrical problems, including an excessive voltage supply. Motor insulation failing prematurely due to high temperatures. A weak blower capacitor.
Can a bad blower motor cause the resistor to go bad?
In the scheme of air conditioning and heater parts, this is one of the least expensive to replace. The heater blower motor resistor can often go bad because of a bad heater fan, and therefore you often have to replace both the heater blower resistor and the fan. It's also not a difficult part to replace.
Will a blower motor work without the resistor?
Without any power, the motor won't run. As a result, the blower fan stays still and silent, and no air blows out of the vents. There are instances where a bad resistor will prevent the current from reaching the blower motor altogether.
Can a bad blower motor cause the resistor to go bad?
In the scheme of air conditioning and heater parts, this is one of the least expensive to replace. The heater blower motor resistor can often go bad because of a bad heater fan, and therefore you often have to replace both the heater blower resistor and the fan. It's also not a difficult part to replace.
Should I replace the blower motor and resistor at same time?
We do suggest that you replace the resistor at the same time. It may not be critical, but this will keep the system more uniform. The issue may even be related to the resistor. If you know that it is not related to the issue, then you do not have to replace it.
Is there a fuse for blower motor?
How do I test a blower motor resistor?
Place one lead of the Ohmmeter on terminal 1 of the resistor. Place the other lead on terminal 2 and check against specifications. If this circuit is open, showing infinity on the Ohmmeter, the blower resistor must be replaced. Move the lead from terminal 2 to terminal 3 and check this reading against specifications.
How do I know if I need a blower motor or a resistor?
Signs of a Bad Blower Motor Resistor Loss of HVAC fan control (total or certain speeds) The fan only works on its highest speed setting. No air coming from vents. Intermittent or inconsistent fan speed.
How do I know if my blower relay is bad?
If you have a faulty blower motor, you may experience low airflow from the vents, even when the fan is on high. There will be no air coming from the vents if your fan isn't working due to a bad blower motor resistor. Blown relay circuit fuses or melted relays are more serious signs of a bad blower motor relay.
How much does it cost to replace blower motor resistor?
How much does a blower motor resistor cost? To replace the blower motor resistor, it would cost you anywhere between $50 to$150 – this includes the cost of equipment and labor. However, by doing it yourself at home, you can save up to $70.
What is the difference between blower motor and blower motor resistor?
The blower motor resistor is responsible for controlling the blower motor speed. In the past, this was done by varying the voltage supplied to the blower motor. In newer applications, the blower motor resistor is actually a solid state module that sends a varied signal to the blower motor.
Can I drive my car without a blower motor?
Your car's blower motor is not only necessary for the operation of your air conditioner. Without a functioning blower motor your engine runs the risk of overheating.
How do you know if a blower motor resistor is bad?
Signs of a Bad Blower Motor Resistor Loss of HVAC fan control (total or certain speeds) The fan only works on its highest speed setting. No air coming from vents. Intermittent or inconsistent fan speed.
How much does it cost to replace blower motor resistor?
How much does a blower motor resistor cost? To replace the blower motor resistor, it would cost you anywhere between $50 to$150 – this includes the cost of equipment and labor. However, by doing it yourself at home, you can save up to $70.
How do you test an AC blower motor resistor?
Place one lead of the Ohmmeter on terminal 1 of the resistor. Place the other lead on terminal 2 and check against specifications. If this circuit is open, showing infinity on the Ohmmeter, the blower resistor must be replaced. Move the lead from terminal 2 to terminal 3 and check this reading against specifications.
Can a bad blower motor cause the resistor to go bad?
In the scheme of air conditioning and heater parts, this is one of the least expensive to replace. The heater blower motor resistor can often go bad because of a bad heater fan, and therefore you often have to replace both the heater blower resistor and the fan. It's also not a difficult part to replace.
How long do blower motors last in a car?
The blower is supposed to last the entire lifetime of your car. However, situations vary and some climates require the fan to be used too often. Many car owners find themselves having to replace the blower after five years. The quality of the motor used to power the blower matters.
Where is the blower motor relay fuse located?
Under the instrument panel, look under the glove box. On the right side of the fender wall you will find another fuse box. The blower motor fuse is easy to replace.
Why does my car heater only work on full blast?
When a blower resistor fails, the highest fan speed usually is the only one that still works because it essentially bypasses the resistor and receives the maximum amount of voltage. When the resistor is working, it reduces the amount of voltage going to the lower fan speeds so the fan runs slower.
How does a blower motor resistor work?
Blower resistors are resistors which are used to control the fan speed of automotive blowers. The fan speed can be changed either by switching the blower resistor resistance mechanically using a rotating lever, or electronically by the air conditioning system.
What relay controls the blower motor?
In a blower motor, the relay supplies the power that allows the fans to circulate warmed air. Essentially an on/off switch, the blower motor relay's reactions start and end the heating process in HVAC systems by controlling the flow of current between the power source and the motor.
How do I know if my blower motor capacitor is bad?
All electricity going to the motor passes through the capacitor, even after it's running. A bad capacitor might cause your blower motor to run slower than normal, run hot, and short cycle. If you notice your furnace stopping and starting erratically, it could very well be the capacitor.
How long should a furnace blower motor last?
How much does it cost to replace a blower motor in a car?
What causes a blower motor resistor to overheat?
In BMW cars, the blower motor resistor often overheats due to incorrect current measurements implemented during the design and engineering of the vehicles. This can cause the HVAC fan to not work at all due to motor failure, and it is unable to blow any air out of the vents.
What causes a heater fan to stop working in a car?
In some cars, a failed blower motor resistor can cause a heater fan to stop working completely. In most cases, a blower motor resistor fails due to corrosion or overheating.
Why is my blower motor not working in my car?
In this car, in the highest "4" fan speed setting, the resistor is bypassed and the blower motor is powered directly by the fan switch. That's why in some cars, the blower motor may still work in the "High" speed setting if the resistor is bad.
Why does my fan resistor keep getting hot?
After replacing the majority of the components, the resistor continues to heat up. I’d search for melted insulation or melted connectors in all of the cabling that connects the fan motor, resistor pack, and fan speed switch, as well as any other problems.
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Which is more expensive multi speed or variable speed blower motor?Why does my AC blower motor relay keep blowing?
