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).

What are the symptoms of a worn out blower motor?

One of the symptoms of a worn out blower motor is that it can intermittently produce a loud screeching noise when running. How to test a blower motor? If the blower motor doesn’t work at all, the blower motor itself must be tested first. Typically it’s done by measuring the voltage at the blower motor connector when it’s turned on.

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.

When do you need to replace the blower motor relay?

If the blower motor does not function, car fuses are blown, or relays are melting, you may have to replace the car blower motor relay. 1. Blower motor does not function 2. Blown fuses 3. Melted relay The blower motor relay is the electrical switch that is used to supply the power for the vehicle’s blower motor.

If there is power indicated on high blower speed, but not low or mid range, the problem is the blower resistor. Test for ground at the blower motor if there is power indicated at all ranges, but the motor does not function.

How do you test a blower motor resistor?

The added resistance in the circuit slows down or speeds up the blower motor as needed. Locate the fuse for the blower motor in the owners/service manual. Test the fuse, with the ignition key on, using the 12-volt test light.

How can I tell if my blower speed switch is faulty?

Test for power at all the blower speeds by moving the blower speed switch through all positions. A faulty resistor loses power at different positions on the switch. High blower speed has direct power to the motor from the switch. If there is no power indicated on high blower speed, the problem is most likely the switch or the fuse.

Where does the purple wire come from on a blower motor?

The purple wire comes from the relay/resistors according to fan speed selected. The purple wire should have battery voltage ~ 12V when on hi. At low is might have 5V, M1 7 ish, and M2 9 ish volts. (note mine is not working and I think resistors are bad I get 11.9V on hi 11.73 v on all other speeds lo, m1, and m2.

Why is my front AC blower not working?

I’ve seen many posts from people whose front AC blower would stop occasionally. My wife would kick the wires under the glove compartment and it would start again. It finally failed altogether. Following the advice from other owners, I replaced the blower motor resistor. That didn’t help.

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 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.

What to do if your AC blower is not working?

Disconnect cables to motor and resistor. Remove hose from motor, it should just pull off with little effort. Unscrew motor and resistor. Screw new motor and resistor in. Connect hose to motor. Connect cables to motor and resistor. Turn on car and test AC. Thanks for watching! Loading…

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.

What happens if a heater blower has no power?

A blower motor without power will not be able to produce any air pressure, and as a result the heating and air conditioning system will be left with no air coming from the vents.

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.

How many volts does a blower motor have?

At low is might have 5V, M1 7 ish, and M2 9 ish volts. (note mine is not working and I think resistors are bad I get 11.9V on hi 11.73 v on all other speeds lo, m1, and m2. Anyone ever measure what voltages are normal to speeds ?

Why is there no ground on my blower motor?

It seems, too, that the black ground wire on the blower motor (accessible from just below the dash) has NO ground potential. I ghetto jumpered a 16 gauge wire from the back of the metal clip on the ground wire to the dashboard impact bar/brace and the fan turns at variable speeds with the knob!

Where is the fuse on a blower motor?

Locate the fuse for the blower motor in the owners/service manual. Test the fuse, with the ignition key on, using the 12-volt test light.

What does the blower motor resistor do in a car?

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. 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.

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 causes a blower fan to turn faster?

The lower the resistance of the selected resistor in the pack, the higher the current that flows through the blower fan causing the fan to turn faster. The statements expressed above are only for informational purposes and should be independently verified.

Why does my Chevy Silverado blower motor not run?

If the blower motor runs when all of the terminals were jumped together, it means the circuit between the resistor connector and blower motor is fine as well as the blower’s motor relay, but the blower resistor is bad and needs to be replaced.

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

Our technicians recommend to confirm the resistor is at fault by first checking the operation of the switch. The average cost for a Chevrolet S10 Blower Motor Resistor Replacement is between $77 -$88. Learn More Hvac blower motor won’t turn on, no matter what speed setting it is placed on.

What causes blower motor to quit working on Blazer?

On my 97 Blazer, the blower motor will suddenly quit working while the anti-lock brake light will simultaniously light and the cruise will switch off. A half hour later, all three will switch back on.

What to do if your blower motor only works on high speed?

If your blower only operates on its highest speed, chances are you have the series type of blower motor resistor. This is the most common failure mode. To repair the problem, simply replace the resistor block. It’s usually located in the ductwork (to keep the coils cool) below the glove box.

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.

Where do I replace the resistor on my blower motor?

To repair the problem, simply replace the resistor block. It’s usually located in the ductwork (to keep the coils cool) below the glove box. Unplug the electrical connector, remove the screws and replace the unit. Replacement blower motor resistor blocks are usually available from any auto parts store or the dealer.

Why does heater blower motor increase in resistance?

As part of our comfort and luxury, the blower speed is one of the most adjusted settings in a car, and so the resistance of the blower motor is constantly being put under stress, which can eventually lead to motor failure; too much humidity in the atmosphere can lead to an increase in resistance.

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.

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.

Where does the power transistor go in a blower motor?

The power transistor has 4 wires: two come from the climate control system control unit, one is the ground, one goes to the negative terminal of the blower motor. The service manual advises measuring the voltage at the blower motor, then if not OK, at the power transistor and so on.

What kind of resistor does a blower fan use?

The newer style of blower resistor uses electronics to send small pulses to the blower motor and based on how frequent the pulses are can speed up and slow down the blower fan. Blower motors can be fairly cheap if they are a manual resistor block style.

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

If your blower motor only works on certain speeds or is stuck on one speed, you may have a problem with the blower motor resistor. O’Reilly Auto Parts has replacement blower motor resistors to fit most cars, trucks and SUVs.

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.

How to replace blower motor resistor O’Reilly Auto Parts?

O’Reilly Auto Parts has replacement blower motor resistors to fit most cars, trucks and SUVs. When autocomplete results are available use up and down arrows to review and enter to select. Touch device users, explore by touch or with swipe gestures. When autocomplete results are available use up and down arrows to review and enter to select.

Which is the best blower motor resistor for ignition?

Read reviews for MasterPro Ignition 9 Terminal Blower Motor Resistor When autocomplete results are available use up and down arrows to review and enter to select. Touch device users, explore by touch or with swipe gestures. 5 out of 5 stars. Read reviews for MasterPro Ignition Blower Motor Resistor

What causes a bad or failing blower motor relay?

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. Any sort of electrical spikes or excessive current…

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.

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.

Where is the blower motor resistor on a Mazda 5?

In many cars it’s fairly easy; the blower motor is located behind the glove box and held by 3-4 screws. In others it might be located inside the dash (e;g Mazda 5) which makes replacement difficult. If you need a proper diagnostic procedure, we posted several links where you can access a service manual for your car for a subscription fee.

Why is the resistor not working on my blower?

Hi There, The resistor is what controls the speed of the blower motor, not the relay. The blower motor relay supplies power to this motor when you turn the switch to “on” that can sometimes fail. When this happens, you may notice that you will not feel anything blowing out of the vents at all.

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.

How many ohms does a blower motor resistor need?

According to the service manual, it must be around 4-5 ohms. In our case the ohmmeter shows open circuit, which means the resistor has failed. Sometimes, a blower motor resistor might fail due to problems with the blower motor itself.

What to do if your blower fan is not working?

Blower Motor Resistor Replacement – YouTube Blower fan not working – 2004-2014 Ford F-150 and other models. Blower Motor Resistor Replacement If playback doesn’t begin shortly, try restarting your device.

Why is the resistor on my Ford Escape not working?

For example, as you can see in this photo, the blower motor resistor in this Ford Escape has failed due to corrosion. If the resistor shows no visual damage, the resistance between terminals must be checked and compared to specifications. If the resistance is out of specs, the resistor must be replaced.

Why does my Ford F 150 fan not work?

Replaced the blower motor resistor and the fan still will not work – where is the blower mtor in my 2010 F 150 so I can Replaced the blower motor resistor and the fan still will not work – where is the blower mtor in my 2010 F 150 so I can – Answered by a verified Ford Mechanic

When do you need to replace the fan resistor?

If your interior AC/ Heat fan is not working on low, or one of the fan settings is not working, then you probably need to replace the blower motor resistor. This video will go though all of the steps. Is your blower fan working only on the max (4 speed)? This is a common problem with the Volkswagen, Audi, Seat, Skoda cars.

What to do if your AC or heater is not blowing?

If your Blower Motor for the AC or Heater suddenly stopped blowing, look here first, it might save you several dollars. Situation, we have a friend that owns a 2017 Chevy Trax LT, she is a nurse who works with my wife, single mom and on a single mom budget.

What happens if you have a bad 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 can cause heater not work?

The most obvious reason an electric heater doesn’t work is that it’s not receiving any power . Start by checking the circuit breaker to see if it has been tripped. If it has, it’s an easy fix – simply turn it off and turn it back on again. You may also have to replace the fuse if it has blown.

Why is my AC heater not working?

The potential issues here vary whether your heating has gone out or your car’s AC system is on the fritz. Common reasons for the heating system not to work include the following: Low coolant. Air in the coolant system. Malfunctioning heater core. Failed (or failing) thermostat.

Why is my furnace blower motor not working?

Another common problem with furnace blower motors not working is caused by the “three D’s”; dust, dirt and debris. These three alone can cause overheating of the motor, which in turn causes the windings and bearings to burn up quicker. Dirt, dust and debris can cause the blower motor to overheat and seize up.

Why would a car heater stop working?

Here are a few of the more common reasons that’s causing the car heater to not work properly: The amount of coolant in the system is too low. When your vehicle’s engine has cooled down, open the radiator cap and check the level of coolant.

What to do if your blower motor is wrong?

If the wrong blower motor is installed for the specific vehicle application, the blower motor circuit components will be damaged. Use only the correct blower motor listed for the specific vehicle application in the Ford Catalog Advantage(TM) or equivalent. 1. Remove the junction box cover.

How is a blower fan connected to a battery?

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. The blower resistor is connected in series to the blower fan motor.

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 is the blower motor not working on my car?

My car has an automatic transmission. Hi There, The resistor is what controls the speed of the blower motor, not the relay. The blower motor relay supplies power to this motor when you turn the switch to “on” that can sometimes fail. When this happens, you may notice that you will not feel anything blowing out of the vents at all.

What kind of wiring does a blower motor use?

240 Volt Psc Blower Motor Fan Speeds- Wire Colors, Speed Selection – Blower Motor Wiring Diagram Blower Motor Relay Fuse – Taurus Car Club Of America : Ford Taurus Forum – Blower Motor Wiring Diagram Ge Fan Wiring Diagram | Wiring Diagram – Blower Motor Wiring Diagram

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 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.

Why does my Lincoln Navigator have a blown fuse?

Fuses and circuit breakers protect your vehicle’s electrical system from overloading. If electrical components in the vehicle are not working, a fuse may have blown. Check the appropriate fuses before replacing any electrical components. Look carefully at the fuse – a broken wire within the fuse identifies blown fuses.

Why is my blower not working on speed 5?

If your blower is not working on speed 5 then the blow motor resistor (I think its called that) is burnt and you need a new one. It is a 5 minute fix.

How does the speed of a blower motor work?

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.

How does a 3 speed blower motor work?

Older style blower motor resistor with exposed resistor elements. The blower motor resistor is what’s responsible for giving you three blower speeds. The resistor block contains three different high resistance coils. Think of these coils like a filament in a light bulb.

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.

Why is my furnace blower not working?

One of the most common problems with furnace fans is a bad blower relay . The first thing to do is check the relay or voltage from the board. If no voltage is recorded, you will have to replace the board or the relay. If there is a battery, check if it is working properly. This is another common reason behind faulty blower fans.

Why is my AC blower not working?

A common problem behind an air conditioner blower not starting includes overheating, which keeps the motor from running. Let your air conditioner rest and cool down for a while before trying to turn it on again; if the motor works at that point, overheating is probably the problem.

Why would a car fan not blow?

Problems like a fan clogged with dirt, a dead motor, a loose fan belt or a stuck wheel can all cause your blower to not work properly. These problems can keep the blower fan from blowing enough air out of your vents to keep you cool.

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.

Is the speed of the blower controlled by the resistor?

The blower speed can be adjusted in almost every modern car. Some cars have blowers that have 4 to 5 fixed speed settings that can be selected, but in this case, the speed of the blower motor is controlled by a blower motor resistor. 1. No air blowing through vehicle’s vents

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 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.

What happens when you replace the resistor on a Sebring?

Re: I replaced resistor and the blower still does not… You can’t post conmments that contain an email address. 2000 chrysler sebring had battery light on yesterday. Door won’t even lock with the key. Cleaned the battery cables and it started first thing this morning.

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.

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.

The main symptom of a failing blower motor resistor is that your fan speed will only work on the high setting. If your fan doesn’t work at all, then there is most likely a blown fuse, issue with the blower motor, hvac panel problem, or a fault in the wiring.

Can a blower resistor be replaced on a Ford Ranger?

Video tutorial on how to replace the blower motor resistor on a Ford Ranger. This is a fairly common issue amongst Rangers, Explorers, and most likely the Mazda B series trucks as well. The main symptom of a failing blower motor resistor is that your fan speed will only work on the high setting.

When did Ford F150 wiring diagram come out?

Ford f150 wiring diagram 2004 2008. It shows the elements of the circuit as simplified forms as well as the power and signal connections in between the tools. With that said failed blower resistor assemblies dont solve all of the possible failures. A wiring diagram is a streamlined traditional pictorial representation of an electric circuit.

Why does my Ford Ranger fan not work?

If your fan doesn’t work at all, then there is most likely a blown fuse, issue with the blower motor, hvac panel problem, or a fault in the wiring. This particular vehicle I am working with here today is a 1998 Ford Ranger, so there maybe some variations between the years and models.

What kind of fan is in a Ford 150?

Used 2004 ford f 150 lariat 4×4 truck for sale 34630a used 2004 ford f 150 svt lightning rwd truck for sale 36165 1998 ford f 150 wiring diagram auto.

What are the electrical symbols on a Ford F150?

The electrical symbols not lonely play where something is to be installed, but along with what type of device is swine installed. For example, a surface ceiling spacious is shown by one symbol, a recessed ceiling vivacious has a different symbol, and a surface fluorescent roomy has option symbol.

What to do if your blower motor wont start?

You can test by testing with a voltmeter set to “Volt AC” between the high-speed blower wire (usually black) and the white neutral wire. If you are getting 120 volts to the motor and it is not starting then you have a blower motor problem and either need another new blower motor or a new blower motor run capacitor.

Why does my furnace blower not come on?

I have an older Maytag furnace that will fire up but the blower motor doesn’t come on, after a minute the the limit switches will turn of the furnace because it will get to hot. I already replaced the motor, the limit switches, and the motor board but I still have the same problem.

How can I tell if my AC blower motor is broken?

Air Conditioner Blower Motor Won’t Turn On. If you turn on your air conditioning system and find that there is no air blowing out of the AC unit, or no buzz of the blower fan motor, then it is possible the AC blower motor has an issue. This is one of the most common and easy ways to know if your air conditioner blower motor is broken or not.

What are the symptoms of blower motor failure?

Lack of air from the vehicle’s vents
Stuck on specific settings
Stuck at one speed

Is my blower motor bad?

No air from the vents. No air flow from the vents when the heater or air conditioning is activated is another symptom of a bad blower motor. If the heater blower motor burns out or short circuits, it will not function, and therefore will not be able to produce any airflow for the system. The blower motor will usually have to be replaced in order…

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 happens if you lose the blower motor relay?

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. The blower motor relay controls the current used to power the blower motor,…

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?

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 should I do if my Bentley Blower Motor is not working?

You say you’ve checked the fuse and replaced the resistor. Wiring rarely breaks, so the next logical step is to access the fan motor per instructions in the Bentley service manual and use a multimeter to check for power at the fan motor connector when the switch is on.

Can a blower fan fail on an AC heater?

It fails less often, but it can fail. The heater/ac blower does not come on. Can hear AC compressor kick on, but just no blower fan. The electronic display for fan just goes up to full then back down. Checked fuse, okay; checked volts at wiring leads have full 12volts.

What to do when your AC Fan is not working?

Checked for incoming resistance ground to the blower, from the dash control switch and it works. Checked for battery at the blower, when the car is running. There is no battery to operate the blower. Rotated all the PDC relays around, they have the same ID, other than ABS pump.

What does it mean when your radiator fan is not working?

This is what we call a blown fuse. A blown fuse is no big deal, and changing one does not cost a lot of money. If your car’s radiator fan is non-functional, check your car’s user manual and locate the fuse for the radiator fan controller or the fan.

Where is the fuse for a 30 volt fan?

On the top flap of the fuse box under the hood is has a diagram for the fuses and relays. I checked the 30 volt fuse which had the picture of the fan and the relays for fan 1 and 2. The fuse for the 30 volt use has no power going to it. Is right next to the fuse for the battery.

This is what we call a blown fuse. A blown fuse is no big deal, and changing one does not cost a lot of money. If your car’s radiator fan is non-functional, check your car’s user manual and locate the fuse for the radiator fan controller or the fan.

Why does my AC fan only work on high?

Your AC only working on high probably has to do with the blower motor resistor. It controls the speed of your fan and if it brakes it will only work on high. Try replacing that resistor first to see if you regain control of the fan speeds.

Locate the fuse for the blower motor in the owners/service manual. Test the fuse, with the ignition key on, using the 12-volt test light.

How do you test for ground at the blower motor?

Test for ground at the blower motor if there is power indicated at all ranges, but the motor does not function. Most blower motors ground through the case of the motor when it is screwed into place or by a small ground strap from the case to the body of the car.

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

How to replace a blower motor in a Ford?

Use only the correct blower motor listed for the specific vehicle application in the Ford Catalog Advantage(TM) or equivalent. 1. Remove the junction box cover. 2. Disconnect the blower motor electrical connector. 3. Remove the 3 blower motor screws. 4. Remove the blower motor. 5. To install, reverse the removal procedure.

Where is the resistor for the blower motor located?

Two individual resistors make up the blower motor resistor assembly on your Chevy pickup. As you’re probably already aware, these resistors are located between the A/C-Heater control panel and the blower motor . The purpose of these resistors is to reduce the amount of the blower motor’s current that’s passing through them.

What does blower motor resistor do?

What is the function of blower motors?

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. Function. Blower motor resistors contain controls that determine air settings. Repair.

What does a heater blower resistor do?

Over the last ten years or so, motor manufacturers have introduced more sophisticated Heater Blower Resistors to control the blower fan motor for the heater and, on many, the digital aircon too. The Heater Resistor is also known as the Resistor Pack or Rheostat. which is designed to keep the internal electronics cool and working efficiently.

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 happens if the blower motor only works on high speed?

In other designs, the failure of 1 resistor means you lose only one speed. However, most car makers bypass the blower motor resistor completely when you move the fan speed switch to high. If your blower only operates on its highest speed, chances are you have the series type of blower motor resistor. This is the most common failure mode.

In many cars it’s fairly easy; the blower motor is located behind the glove box and held by 3-4 screws. In others it might be located inside the dash (e;g Mazda 5) which makes replacement difficult. If you need a proper diagnostic procedure, we posted several links where you can access a service manual for your car for a subscription fee.

At low is might have 5V, M1 7 ish, and M2 9 ish volts. (note mine is not working and I think resistors are bad I get 11.9V on hi 11.73 v on all other speeds lo, m1, and m2. Anyone ever measure what voltages are normal to speeds ?

How to troubleshoot an air handler and blower unit?

Check thermostat to see that it is calling for heat or cooling, service switches at the equipment, check fuses or circuit breakers serving the equipment; for cooling systems check for a condensate drip tray overflow switch that may have turned off the system. see REPAIR GUIDE for AIR CONDITIONERS.

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 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.

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.

What to do if your air conditioner blower motor is not working?

Other options include removing the air conditioner blower motor from the AC unit and checking the label on the actual blower motor. Write this part number down for easy reference. Having the exact part number can save you both time and money, especially if you intend to get a professional installer to replace the blower motor for you.

When a switch, a resistor, and a load are wired in series, the resistor “drops” some of the voltage passing through it, effectively reducing both current flow and voltage at the motor. A voltmeter connected to both ends of a resistor while current is passing through it to a load will measure the amount of voltage being “dropped” by the resistor.

Why is my blower motor resistor not working?