Why does my blower motor keep blowing fuses?

Blown fuses 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.If the fuse keeps blowing and you’re also hearing strange sounds coming from your furnace, the problem could be traced back to any of these components: A malfunctioning blower motor that draws too much power and causes a short. A starting capacitor that’s failing and causing intermittent electrical issues.

What would cause a fuse to keep blowing?

Overloaded Circuit The most common cause of a blown fuse is when something draws too much power from the circuit. This is most often caused by either too many lights or from using too many plug-in appliances at once. The biggest culprit for this kind of issue is a multiple outlet adapter plugged into a socket.

How do you fix a fuse that keeps blowing?

Unscrew the blown fuse and replace the fuse with a new one. For circuits, flip the tripped circuit from the center position to the off position, and then flip it back to the on position. Turn the main power back on.

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.

What are the signs of a failing blower motor 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.

Why does my 15 amp fuse keep blowing?

Having too many devices plugged into a circuit is the most common cause of fuses blowing. This is particularly true of power-hungry devices, such as toasters. Most homeowners assume this is what is causing the problem and work around the issue by limiting plugged-in devices.

Why does my 30 amp fuse keep blowing?

In most cases, an amplifier will blow fuses due to internal damage caused by the way it was installed. Many times, an amplifier won't show signs of improper installation until it's too late, and blowing fuses indicates that damage has been done.

How can you tell if a relay fuse is blown?

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 do I test a blower fan 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.

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.

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.

Where is the blower fan resistor located?

The blower motor resistor is usually extremely easy to access, but the hard part can be positioning your body inside the car to remove the part. The resistor is at the bottom of the HVAC housing or just behind the glove compartment.

Can you use tin foil as a fuse?

Gum Wrappers and Fuses The conductor on the gum wrapper is not the only remedy for a blown fuse; an aluminum foil can also work just fine. Basically, any electrical conductor that can be wrapped around the fuse can do the trick.

Can I use wire instead of fuse?

Copper has a higher melting point than the tin used in fuse wire. So, when a high level of current runs through copper wire, it continues to heat but will not melt. Instead, it causes a short circuit - potentially ruining your appliance and sparking a fire.

What happens if I put a higher amp fuse?

If you use a fuse with the wrong amperage, the fuse won't blow as intended, damaging the circuit and resulting in a much larger repair bill. Rather than risk blowing the circuit, take the car to a repair shop to determine what is causing the fuse to repeatedly blow.

Can you replace a fuse with a higher amp?

Do not replace a blown fuse with one that has a higher amperage rating. The fuse has a specific amperage rating because it is intended to be the weak link in the circuit to protect the electrical components. A blown fuse indicates excessive current has entered the circuit.

What comes first fuse or relay?

If you put the fuse after the relay, then that internal short would mean that the live wire from the relay to the battery is not protected. It could then melt and cause a potential fire risk.

How do you know if a relay is damaged?

If you connect the two terminals together, you should hear a click. If it clicks, the coil is good and your relay is working. If it doesn't click, your relay is bad.

How do you know if a relay is bad?

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.

How much does it cost to replace a 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 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.

Is there a relay for 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.

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 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.

What does a blower motor relay do?

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 a blower motor relay fuse to blow?

Blown fuses One of the first symptoms of a bad or failing AC blower motor relay is a blown AC blower motor relay circuit fuse. 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.

Why does my heating unit keep blowing fuses?

Reduced airflow can cause your heating unit to struggle and potentially result in blown fuses. For example, an undersized ductwork or blower motor can be the reason why the blower is not able to carry and circulate sufficient air throughout the home.

Why do my windshield wiper fuses keep blowing?

The common issue with fuses blowing would be because of faulty wiring. The faulty wiring or even the defective wiper motors would often lead to the excessive current flow in a system. What this does is result in a blown fuse each time a new one is installed. If the motors cannot be repaired, then you might have to replace them entirely.

What happens when the blower motor is turned off?

When the blower motor is in the off position, it is removed from the power source. In the highest speed mode, the blower resistors are totally bypassed, and the fan is linked directly to the car’s battery, allowing the motor to draw the greatest amount of electricity possible. Is there a fuse for the motor that blows air?