Easy tips

What happens when a blower motor resistor fails?

What happens when a blower motor resistor fails?

The blower motor resistor is the component directly responsible for controlling the blower motor fan speed. If the resistor shorts or fails, it may cause the blower motor to remain stuck on one fan speed.

Why is my blower motor stuck on one speed?

Blower motor stuck on one speed A common symptom of a faulty blower motor resistor is a blower motor that is stuck on one setting. The blower motor resistor is the component directly responsible for controlling the blower motor fan speed. If the resistor shorts or fails, it may cause the blower motor to remain stuck on one fan speed.

What to do when air blows out of defroster vents?

Assuming that your actuator has failed in the most common position, blowing out of the defroster vents only, you should not have to do anything other than installing the actuator motor. No indexing of the door shafts to the cam/cog or recalibration of the actuator motors.

Where is the blower motor on my car?

The blower motor in your car is under the passenger side dashboard. If you can get to the bottom of the dashboard there should be a plastic panel on the passenger side you can remove to expose the blower motor. There are 4 screws that hold it up under your dash.

Can you use a variable speed blower with an AC compressor?

Variable speed blowers deliver maximum comfort and efficiency when paired with a variable speed compressor. You can pair a variable speed blower with a single-stage or two-stage AC compressor and enjoy a modest boost in comfort and efficiency. What about furnaces?

How is the speed of the blower motor controlled?

The electronic module that controls the speed of the blower motor is called a blower motor control module. In some cars, the blower motor has only 4 or 5 fixed speeds. In this case, the speed of the blower motor is controlled by a blower motor resistor.

What are the symptoms of a failed blower motor resistor?

Blower motor resistor problems. Problems with a blower motor resistor are common in many cars. The most common symptom of a failed blower motor resistor is when the heater fan only runs at high speed and doesn’t work at low speeds.

How much does it cost to replace a blower motor resistor?

The blower motor resistor or control module replacement is not very expensive. For example, one of our colleagues had a problem with his 2011 Ford Escape: the fan only worked at the speed 4. He paid $50 to diagnose and $112 to replace the resistor at a local Ford dealership.

Why does my blower fan only work on one speed?

by Lee Sallings. The most common symptom of a faulty blower motor resistor is a blower fan that only works on one speed, usually high. This can be annoying, but troubleshooting is easy. If you start at the blower motor, and check resistance in the circuit, you will find the problem in no time.

The blower resistor is connected in series to the blower fan motor. This means that the current running through the blower motor, and its’ speed is therefore controlled by the resistor value. The user chooses a fan speed by selecting a speed which then connects one of the resistors in the blower resistor pack.

What are the symptoms of a bad heater motor resistor?

Symptoms of a Bad or Failing Heater Blower Motor Resistor. 1 1. Blower motor stuck on one speed. A common symptom of a faulty blower motor resistor is a blower motor that is stuck on one setting. The blower 2 2. Blower motor does not work on certain settings. 3 3. No air from the vehicle’s vents.

by Lee Sallings. The most common symptom of a faulty blower motor resistor is a blower fan that only works on one speed, usually high. This can be annoying, but troubleshooting is easy. If you start at the blower motor, and check resistance in the circuit, you will find the problem in no time.

The blower resistor is connected in series to the blower fan motor. This means that the current running through the blower motor, and its’ speed is therefore controlled by the resistor value. The user chooses a fan speed by selecting a speed which then connects one of the resistors in the blower resistor pack.

If you’ve replaced a blower motor resistor and that replacement has failed, it’s time to conduct an amperage test on the blower motor. If the amp draw exceeds manufacturer’s specifications, replace the blower motor. can also cause an overheating condition. In some cases, the heat is so high that it melts the connector.

What causes a blower motor to overheat?

Decreased airflow causes the blower motor resistor to overheat and fail. Reduced airflow also causes the blower motor to work harder, draw more current and that can cause repeat blower motor resistor failures. Blower motor is drawing too much power. Check the cabin air filter for clogging.

What does a blower motor do in an air conditioner?

What Is a Blower Motor? The blower motor is a component in your HVAC system that blows the conditioned air through the vents in your home. It takes the cool air created by your air-conditioner and circulates it throughout your indoor space to ensure that the temperature reaches the level dictated by the thermostat.

What should I do if my blower motor is not working?

If it’s good, refer to a wiring diagram for your vehicle and conduct these tests: Disconnect the electrical connector at the blower motor and jumper power and ground to the motor, bypassing all the speeds controls.

If you’ve replaced a blower motor resistor and that replacement has failed, it’s time to conduct an amperage test on the blower motor. If the amp draw exceeds manufacturer’s specifications, replace the blower motor. can also cause an overheating condition. In some cases, the heat is so high that it melts the connector.

Symptoms of a Bad or Failing Heater Blower Motor Resistor. 1 1. Blower motor stuck on one speed. A common symptom of a faulty blower motor resistor is a blower motor that is stuck on one setting. The blower 2 2. Blower motor does not work on certain settings. 3 3. No air from the vehicle’s vents.

Decreased airflow causes the blower motor resistor to overheat and fail. Reduced airflow also causes the blower motor to work harder, draw more current and that can cause repeat blower motor resistor failures. Blower motor is drawing too much power. Check the cabin air filter for clogging.

Why does my HVAC blower need to be replaced?

The blower motor is the part of your HVAC system that uses the most energy, so it may very well be the culprit if you see a significant rise in your utility bills. An aging, problematic, or dirty motor has to work harder to properly circulate conditioned air throughout your home, which leads to higher energy consumption.

Why does my Dakota blower resistor keep going bad?

When your Dakota or Durango left the factory, it had a Mopar motor and voltage resister that were compatible with each other. After 10-15 years the motor wears out , begins to draws more amps burns up the resister. Most people replace the wiring harness and the resister with. cheap replacement from Autozone / Advanced etc.

Where is the relay on a blower motor?

Correction assuming 97 is same (probably is)… Fan relay is as posted before on top of the duct work left of the resistors you can see both behind the glove box if you take it out. The purple wire comes from the relay/resistors according to fan speed selected.

Why is my blower motor not coming on?

With the back wire hooked up I ran a jumper directly to the battery pos and attached it the purple wire terminal on the motor. The motor did not come on. So either my motor is dead shorted or something has gummed up the brushes or they are worn out.

Where does the power go in a blower motor?

For each higher speed, power flows through one less resistor. Some car makers run blower motor power through the fan speed switch first, then through the blower motor resistor and then to the blower motor and ground. Other car makers reverse that and run power to the blower motor first and terminate ground at the blower fan speed switch.

What kind of blower circuit does Dodge Dakota have?

Here is a the blower circuit for a 2002 Dodge Dakota. Hopefully it is the same for your particular year model.

Why does my blower resistor keep going bad?

Trent, one of the biggest reasons for blower motor resistors to have shorten life is actually because of faulty blower motor drawing too many amps, some times melting wires/plugs, heating up resistors shortening their life. Many Dodge forums tell of this problem.

For each higher speed, power flows through one less resistor. Some car makers run blower motor power through the fan speed switch first, then through the blower motor resistor and then to the blower motor and ground. Other car makers reverse that and run power to the blower motor first and terminate ground at the blower fan speed switch.

Why does my Dodge Dakota blower keep going bad?

If you leave the blower motor switched continually on you may not notice this. If so I suspect that there is an earth fault on one of the wires connected to either pin 4 or 5 of the resistor. Here is a the blower circuit for a 2002 Dodge Dakota. Hopefully it is the same for your particular year model.

The blower motor resistor or control module replacement is not very expensive. For example, one of our colleagues had a problem with his 2011 Ford Escape: the fan only worked at the speed 4. He paid $50 to diagnose and $112 to replace the resistor at a local Ford dealership.

Can a broken motor switch stop a blower?

A broken blower motor switch can also stop the blower from changing to certain speed settings. If your blower motor cannot change to certain speeds, check both the resistor and the switch on your dashboard. The most common failure points are the resistor and the motor itself.

Why does blower motor resistor keep going out?

The blower motor appears to be defective here. When the brushes wear out the motor draws excessive amps which could cause the resistor to burn out. Before making further replacements remove the motor and check it, especially the brush assembly. This is the most likely reason for the resistor to fail repetitively.

What does a blower motor resistor do?

Definition. A blower motor resistor, typically located beneath the passenger side dashboard, contains three resistors, or sets of terminals designed to generate voltage in proportion to electrical current. These resistors allow the blower motor to function at lower speeds.

What is an AC resistor?

Resistor AC Response. For ordinary currents and frequencies the behavior of a resistor is that of a dissipative element which converts electrical energy into heat. It is independent of the direction of current flow and independent of the frequency. So we say that the AC impedance of a resistor is the same as its DC resistance.

What happens if heater blower motor does not work?

Therefore, if major problems in the heating and air conditioning system fail, as if the power supply to the motor was completely cut off due to overheating or corrosion, the motor will simply not work, which in turn will render the entire heating and air conditioning system unusable, as no air will flow through the vehicle’s air vents. 2.

The blower motor resistor is the component directly responsible for controlling the blower motor fan speed. If the resistor shorts or fails, it may cause the blower motor to remain stuck on one fan speed.

Blower motor stuck on one speed A common symptom of a faulty blower motor resistor is a blower motor that is stuck on one setting. The blower motor resistor is the component directly responsible for controlling the blower motor fan speed. If the resistor shorts or fails, it may cause the blower motor to remain stuck on one fan speed.

How to notice bad resistor in Toyota blower or fan?

How to notice bad resistor in Toyota blower or fan. Issues in fan or blower speeds. – YouTube If playback doesn’t begin shortly, try restarting your device.

How is the speed of a blower fan controlled?

The blower resistor is connected in series with the blower fan. This means that the current running through the blower motor, and thus is speed is controlled by the resistor value. The user chooses a suitable fan speed by using a selector to connect one of the resistors in the blower resistor pack.

What happens when the blower motor does not work?

Case Details: The blower motor does not work though it was independently checked and found to be OK. All fuses are good. If the blower motor is not working when attached to the circuit, the resistor unit is more likely to be at fault. The resistor unit is differently located on various motors but will either be on the motor base or the heater body.

How to replace a blower motor resistor thermal fuse?

Blower Motor Resistor Thermal Fuse Replacement 1 Order the Correct Fuse. The part I ordered is from NTE Electronics. 2 Remove Old Fuse. Now the instructions say to use the crimps and only make mechanical connections. 3 Continue Removal. 4 Tin. 5 Solder the Crimps. 6 Add the Fuse. 7 Rinse and Repeat. 8 Another Shot

What to do if your blower fan stops working?

Take glove box out on passenger side. Upper left corner is Blower Fan Knock on it. If it comes on it is going out will need to replace. Blower fan will not come on at all? Check Fuses & Blower Fan? Fuses replaced for blower fan,took blower fan out and tested it and it worked? Well it has to be you climate control panel nothing else to check!

How does a blower motor resistor pack work?

The way the resistor pack does this is by shortening or lengthening the circuit through the coils to add or subtract the amount of resistance it takes to get the speed you want. So naturally, three speeds, four pins.

What happens when a heater motor resistor fails?

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. 2. Blower motor does not work on certain settings

What does it mean if your blower motor is not working?

Average rating from 849 customers who received a AC is not working Inspection. The blower motor resistor is an electrical component that is a part of the vehicle’s heating and air conditioning system. It is responsible for controlling the blower motor’s fan speed.

What does the resistor on a heater do?

It is responsible for controlling the blower motor’s fan speed. When fan speed is changed via the knob on the instrument cluster, the blower motor resistor changes setting, which changes the speed of the blower motor.

What should be the value of a blown resistor?

If your resistor has colours of Green – Black – Black – Gold – Brown it should be a value of 50 Ohms (5+0+0 x 0.1)with a tolerance of +/- 1% (I cannot see the second colour band that well in your picture to be sure of its colour so not entirely sure of its value therefore the resistor value is somewhere between 50-59 Ohms)

If any of these resistances show an open circuit, then the blower resistor desires to get replaced. Know what fee you should pay to get your automobile constant. The average cost for a blower motor resistor substitute is between $80 and $150. Labour costs are envisioned among $35 and $80 even as elements are priced between $50 and $75.

Can a blower motor resistor be blown out?

A car which is not maintaining temperatures properly may be suffering from a blown blower motor resistor. If your car is in need of a new resistor, you want to shop from among the best blower motor resistors for cars and trucks to find the ideal option for you.

A broken blower motor switch can also stop the blower from changing to certain speed settings. If your blower motor cannot change to certain speeds, check both the resistor and the switch on your dashboard. The most common failure points are the resistor and the motor itself.

Why does my blower motor only work at slow speed?

Blower motor only working on low speed. Another common symptom of a faulty blower motor resistor is that the blower motor only works at slow-speed. This can be caused because of bad wiring between the blower motor resistor and the blower motor itself.

What are the symptoms of a bad blower motor resistor?

Blower motor stuck on one speed. A common symptom of a faulty blower motor resistor is a blower motor that is stuck on one setting. Blower motor does not work on certain settings. No air from the vehicle’s vents.

Why does the blower motor resistor keep blowing?

The blower motor is probably worn out and drawing too much current causing the resistors to blow. Check that and the plug up to the blower and resistor for any melted wires.

What is a blower motor resistance?

Why is my Ford Escape blower not working?

If playback doesn’t begin shortly, try restarting your device. An error occurred. Please try again later. (Playback ID: H7mycP02T8HupY00) Videos you watch may be added to the TV’s watch history and influence TV recommendations. To avoid this, cancel and sign in to YouTube on your computer. An error occurred while retrieving sharing information.

What should I do if my fuse keeps blowing?

The process on overall is quite simple and it would be done within minutes. You would simply have to pull out the blown fuse and replace it with a new one. One thing you have to keep in mind is to replace the blown fuse with one having the same ampere rating. #1 Start by locating the fuse panel.

When your Dakota or Durango left the factory, it had a Mopar motor and voltage resister that were compatible with each other. After 10-15 years the motor wears out , begins to draws more amps burns up the resister. Most people replace the wiring harness and the resister with. cheap replacement from Autozone / Advanced etc.

When do you replace the fan control AMP?

If that checks out replace the blower motor. If you don’t see a change in voltage on terminal 2 of the blower motor when adjusting the fan control knob than check for power on terminal 2 of the fan control amp and for ground on terminal 1. If you have power and ground replace the fan control amp.

How much does it cost to replace a blower motor?

Motor type. Standard blower motors operate at a single speed and cost around $450 to replace, including parts and labor. Variable-speed motors cost $600 and up to replace.

How much does an AC blower motor cost?

The costs to replace the furnace blower motor will depend on a few factors, including the type of blower motor required, the contractor you decide to hire and your geographical region. Based on these factors, the costs, including both parts and labor, can range anywhere from $250 to more than $500 for a standard single speed blower motor.

Where exactly is the blower motor resistor?

Usually it’s located in the dashboard on the opposite side of the steering wheel. You can’t see it because it’s inside the vehicle, but that’s where it is located. The blower motor resistor is the part of the blower motor that controls the speed.

What happens if you have a bad blower motor resistor?

If you have faulty blower motor resistor you may experience low airflow coming from the vents even when the fan is all the way on high. In some cases bad blower motor resistor may not even turn the blower motor fan as a result your fan will not work at all and there will be no air coming from the vents.

What to do if your heater motor resistor is failing?

If your vehicle is displaying any of the symptoms above, or you suspect that your blower motor resistor may be having an issue, have the vehicle inspected by a professional technician, such as one from YourMechanic, to determine if the component should be replaced.

How does a high speed blower motor work?

In the highest fan speed state, the blower resistor is bypassed completely and the fan is effectively connected directly to the car’s battery, allowing maximum current to be supplied to the blower motor.

What causes a blower fan to not work?

When this happens, you may notice that you will not feel anything blowing out of the vents at all. This may also cause the blower motor to work intermittently. A blower fan is connected to the negative battery terminal (also called ground) on one end and to the positive battery terminal through a blower motor resistor on the other end.

Where can I get a new blower motor resistor?

I replaced the blower motor resistor and the control unit with new parts from rockauto (ACDelco). I’ve checked the fuse in the dash fuse panel and it is good.

Why does my blower motor resistor keep breaking?

If water spray enters the system, it can quench the hot resistor wires, causing them to break. If you notice the loss of one blower motor speed or all speeds soon after driving through rain, suspect water damage to the blower motor resistor. Alldatadiy.com and Eautorepair.net are professional-grade shop manuals—period.

When this happens, you may notice that you will not feel anything blowing out of the vents at all. This may also cause the blower motor to work intermittently. A blower fan is connected to the negative battery terminal (also called ground) on one end and to the positive battery terminal through a blower motor resistor on the other end.

When to replace the resistor on a heater?

If your fan speed control does not seem to work you may want to replace this fan speed control component. While the switch could have been the issue I also had a squealing blower motor and oftentimes you’ll burn up a resistor when running a squealing heater fan motor.

Why does my GM blower motor resistor keep failing?

In some cases, the heat is so high that it melts the connector. This is common on late model GM vehicles. If you discover a melted connector, do NOT attempt repair. Purchase an upgraded pigtail and splice it into the harness along with a new blower motor resistor.

When did the blower motor on my Blazer stop working?

2005 T’Blazer, 6 cylinder, manual A/C controls. Maybe 6 months ago, blower fan speed 5 stopped working, followed by the rest shortly after. Following the great advice on this forum, I checked the blower motor resistor and plug, and replaced as advised.

2005 T’Blazer, 6 cylinder, manual A/C controls. Maybe 6 months ago, blower fan speed 5 stopped working, followed by the rest shortly after. Following the great advice on this forum, I checked the blower motor resistor and plug, and replaced as advised.

What happens when a cooling fan relay fails?

If the relay fails, it will be unable to supply power to the fans, and as a result they will not operate. This can lead to overheating, especially when the vehicle is at a stop, where there is no forward motion by the vehicle to pass air over the radiator. 3. Cooling fans stay on at all times

If your vehicle is displaying any of the symptoms above, or you suspect that your blower motor resistor may be having an issue, have the vehicle inspected by a professional technician, such as one from YourMechanic, to determine if the component should be replaced.

If the relay fails, it will be unable to supply power to the fans, and as a result they will not operate. This can lead to overheating, especially when the vehicle is at a stop, where there is no forward motion by the vehicle to pass air over the radiator. 3. Cooling fans stay on at all times

Why are my cooling fans running at all times?

3. Cooling fans stay on at all times. If the cooling fans are staying on at all times, this is another (less common) symptom of a possible problem with the cooling fan relay. If the relay shorts internally, it may cause power to be permanently switched on, which will cause the fans to run at all times.

What to do if your blower resistor Burns?

Look for obvious signs of corrosion and burns from overheating. If you see signs of overheated connectors, replace the blower resistor and its connector, but again, you must splice the wires right, or you’ll have problems at the splice later on.

How much does a blower motor resistor cost?

Depending on the manufacturer and model, a blower motor resistor can go anywhere between $3 and $335 on CarParts.com. The replacement parts come in individual units, sets of two resistors, or as part of a blower motor resistor kit.

How does a blower motor resistor control the fan speed?

The blower motor resistor controls the fan speed of the blower motor and the resulting change in air pressure produced by the movement of the blower fan. It accomplishes this by regulating the electric current that powers the motor.

Look for obvious signs of corrosion and burns from overheating. If you see signs of overheated connectors, replace the blower resistor and its connector, but again, you must splice the wires right, or you’ll have problems at the splice later on.

Why is my blower motor resistor not working?

CLICK HERE TO RESET YOUR PASSWORD! Help! Fan quit working on all 4 speeds. AC light & recirc light still light up and AC compressor clutch engages when turning fan on in AC mode, but not getting the fan to work. I replaced the blower motor resistor and the control unit with new parts from rockauto (ACDelco).

When do you Know Your HVAC blower motor needs to be replaced?

For example, squealing or screeching noises may mean that the blower motor has a damaged belt or bearing problems, which can be fixed by replacing the belt or lubricating the bearings respectively. If the motor is making rattling, clanking, or banging sounds, it may be because of a loose or broken part.

What should the voltage be on a blower motor?

If those are OK than backprobe the blower motor connector and check for power on terminal 1. Check terminal 2 for a variable voltage, this should be 12v with the fan control knob on off and 5v or full ground on full. If that checks out replace the blower motor.

How to choose the right air conditioner blower motor?

In order to get the right blower motor for your air-conditioner, the contractor has to take a number of things into consideration, including the type of drive, the diameter of the motor, rotation direction, horsepower, voltage, speeds, and size of the capacitor.

Author Image
Ruth Doyle