The blower motor relay is the electrical switch that is used to supply the power for the vehicle's blower motor. The blower motor is the component responsible for pushing air through the vents of your vehicle's heating and air conditioning systems.The blower motor relay is the electrical switch that is used to supply the power for the vehicle’s blower motor. The blower motor is the component responsible for pushing air through the vents of your vehicle’s heating and air conditioning systems. Without it, the AC system will not be able to circulate any heated or cooled air.
What happens when a blower motor relay goes bad?
If the blower motor relay develops any sort of problem that hinders its ability to properly limit and distribute power, it may cause the blower motor fuse to blow. Any sort of electrical spikes or excessive current from a bad relay will blow the fuse and cut power in order to protect the system.
What does the blower relay control?
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.
What causes blower motor relay failure?
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 do I test a blower motor relay?
Connect a test light or multimeter to the ground (black lead). Turn the ignition key to the on position (engine off), and remove the relay. Using the probe, test all terminal sockets in the relay connector. Two of the four should have power.
What causes blower motor relay failure?
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 do I know if I have a bad blower motor relay?
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 a blower motor relay?
The blower motor is operated by an electrically operated switch, called a relay. If the relay fails, the motor's fans will not blow conditioned air into your car. Fixing the relay usually costs around $50 to $80. So, if the blower motor relay fails, you could be left sweating or shivering.
Is there a fuse that controls the blower motor?
Many vehicles have two fuses for the blower motor, one in the interior fuse block and the other under the hood. The blower motor is usually under the dashboard on the passenger side.
Where is the blower motor relay?
The blower motor relay is generally located in the under-hood fuse box or in the under-dash fuse box. A blown fuse can mimic relay failure. A failed blower motor switch can also give many of the same symptoms.
What happens when blower motor resistor goes out?
If the resistor shorts or fails, it may cause the blower motor to remain stuck on one fan speed. The heating and air conditioning systems may still function at one speed, however the resistor will have to be replaced in order for full functionality to be restored.
How can you tell if you have a bad relay?
You want to feel and listen for any clicks. If you feel and hear clicks, the relay works on one side – the side with the energizing circuit and coil. However, if there was no sound from the horn, the relay has a problem along the contact circuit.
Is there a fuse that controls the blower motor?
Many vehicles have two fuses for the blower motor, one in the interior fuse block and the other under the hood. The blower motor is usually under the dashboard on the passenger side.
What causes blower motor relay failure?
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 do I test a blower motor relay?
Connect a test light or multimeter to the ground (black lead). Turn the ignition key to the on position (engine off), and remove the relay. Using the probe, test all terminal sockets in the relay connector. Two of the four should have power.
Can you drive with a bad blower motor?
Should you drive with a bad heater blower motor? A bad heater blower motor will not affect the safety of your car, with the possible exception of you not being able to clear the windshield of snow, ice, or condensation if the defrosters don't work.
Why is my blower not working in my car?
Find the fuse associated with the A/C blower motor. If the blower motor fuse is still in-tact, your problem is located elsewhere. If the fuse is blown, simply replacing the fuse with an identical fuse of the same amperage rating could get your system working again!
How long does it take to replace a blower motor in a car?
How Long Does It Take To Replace A Blower Motor In A Car? It generally takes about 4 hours for an experienced technician to do a blower motor replacement. If you are doing it on your own in your garage with common tools, you can expect the job to take 6 hours or more.
How long does it take to replace a blower motor?
How long does it take to replace a blower motor? Replacing a blower motor takes 2 to 3 hours on average. The blower motor is typically located behind a control board and other furnace parts.
Does a blower motor have a relay?
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.
What does a heater relay do?
The electric relay in a furnace is responsible for relaying electrical power to the heating elements and the blower motor inside the furnace cabinet. The heating elements provide the heat to warm the air, and the blower motor sends this warmed air through the ductwork.
Should you replace blower motor and resistor at the 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.
What happens if a relay fails?
If the relay fails it will cut off power to fuel pump and ignition system, which will result in a no power, and therefore no start condition.
What does a bad relay sound like?
If your starter relay has gone bad, the electrical signal will never make it from the battery to the starter motor. As a result, your engine won't turn over - no matter how many times you turn the key. A faulty relay often produces an audible clicking sound when you turn your car.
Does a blower motor have a relay?
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.
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.
How does a blower motor relay work?
The blower motor relay is what cuts on the blower to release the cold air into the cabin of the car. When you turn on the switch in your car to activate the air conditioner, the blower relay will turn on and release the power needed to turn on the blower fan. This part of your car is only used when the air conditioner is turned on.
What does a blower motor do in a car?
The blower motor is the main electric motor in the car HVAC system. The purpose of this blower motor is to allowing blowing air to come through the vents by transferring the electrical current. It uses a motor resistor and switch to control the speeds of airflow.
What causes a blower motor to stop working?
Since the relay supplies the current that makes the motor move, a nonresponsive motor may be the result of a worn out relay. The blower motor relay does more than channel electrical current.
What are the symptoms of a bad blower motor relay?
When the blower motor relay does begin to fail, the vehicle will usually display a few symptoms that alert the driver of a potential problem that should be serviced. 1. Blower motor does not function One of the first symptoms of a problem with the blower motor relay is a blower motor that does not function at all.
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