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.
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 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.
When does a blower motor resistor need to be replaced?
If the resistance is out of specs, the resistor must be replaced. For example, in this photo we measured the resistance of this blower motor resistor. 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.
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.
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.
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 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.
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.
Why does my blower only work 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.
What do you need to know about blower motor fan?
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What are the resistors on a blower motor?
Blower resistors are made of several resistors with different resistances. There are also two additional circuits used for the off state of operation as well as the highest speed of operation. In the off state, the blower motor is effectively disconnected from the power supply.
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 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.
Is there a high speed blower motor relay?
Yes there is a high speed relay which sounds like it is out. Here is a guide to help test it and the blower motor wiring diagrams so you can see how the system works with the relay location below as well. Check out the diagrams (Below).
How to prevent repeat failures of blower motor fan?
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How can I tell if my blower motor is working?
If the blower motor works it’s time to check some voltages at the module. There’s a power wire that comes from the control panel. On most models it’s either red or purple. This power in wire should turn on a test light with the ignition on and maximum speed selected. The black wire should indicate a strong ground.
What causes a blower motor to stop running?
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. Over time, the ground connection can become corroded or loose, causing the motor to function intermittently. Lee Sallings is a freelance writer from Fort Worth, Texas.
Where does the ground go in a Honda blower motor?
The blower motor control module (Honda calls it Power Transistor) supplies the ground. 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.
What happens when a blower motor relay wears out?
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, and is subject to the constant on and off switching. Over time, it can eventually wear out.
Where is the blower control switch on the dashboard?
The blower control switch on the dashboard controls the circuit flow of the blower motor to adjust the voltage from low, to medium, to medium-high, to high. When on high, the circuit bypasses the blower resistor.
Why are there so many blower motor problems?
However, they did require a lot of electrical energy. In an effort to increase the efficiency of the climate control systems General Motors experimented with some cutting-edge technologies. Unfortunately, the fallout from this remains a large amount of vehicles with common blower motor problems.
What is the function of the blower motor relay?
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.
How does a blower motor resistor work in a car?
This is done, so the resistor or a control module is cooled down by passing air. In some older cars, a blower motor resistor was installed on the firewall with the access from under the hood. Problems with a blower motor resistor are common in many cars.
The blower control switch on the dashboard controls the circuit flow of the blower motor to adjust the voltage from low, to medium, to medium-high, to high. When on high, the circuit bypasses the blower resistor.
This is done, so the resistor or a control module is cooled down by passing air. In some older cars, a blower motor resistor was installed on the firewall with the access from under the hood. Problems with a blower motor resistor are common in many cars.
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.
How to test a Mercedes Benz fan blower motor regulator?
This is the blower motor resister, which controls the fan speeds. Disconnect the multi-wire connector from the blower motor resister next to the blower motor. Start the car and turn the air conditioning on. Test the connector for power at the terminals in the connector using the voltmeter. If there is power, reinstall the connector to the resister.
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 is a brushless DC motor used for speed control?
Brushless DC motor units have the following features. 1) It has high-efficiency because a permanent magnet rotor is used and secondary loss is small. 2) The rotor inertia can be reduced, and a high-speed response is obtained. 3) It is possible to downsize the motor because it is highly efficient. 4) Speed fluctuations with changing loads is low.
Is there a way to test a blower motor?
Blower Motor Resistor Testing Place one lead of the Ohmmeter on terminal 1 of the resistor. Place the other lead on terminal 2 and check against specifications. Move the lead from terminal 2 to terminal 3 and check this reading against specifications. Move the lead from terminal 3 to terminal 4 and check this reading against specifications.
What is the blower motor in a car?
The blower motor is the fan that pushes heated or cooled air through dashboard vents based on the climate system settings and the fan speed selected. Adjusting the fan speed sends a signal through a resistor to the blower motor to either pick up the pace or slow it down.
What are the parts of a blower motor?
Components of a Blower Motor. The components of a blower motor can vary from one application to another, but they typically consist of: a DC motor. a housing that can be bolted down. a fan (also known as a wheel or cage)
What is DC speed control?
DC drives are DC motor speed control systems. Since the speed of a DC motor is directly proportional to armature voltage and inversely proportional to motor flux (which is a function of field current), either armature voltage or field current can be used to control speed.
Why does my blower motor have a higher amp draw?
If the door is left off during the test, the fan will move more air than it would if it had to pull all its air through the return air ducting. Therefore, the fan will work harder and the amp draw will be higher than it would be under normal operating conditions. 6. Read the amp draw of the blower motor.
Can you change the speed of an air blower?
Yes you can but we think its just better to know that it can be done whats involved with a simple speed change of your air blower for your furnace air conditioner or heat pump. Ryan from Environmental Heating & air of nc gives you the color codes and speed of those wires.
How to measure blower motor AMP draw by contracting business?
Disconnect power from the blower motor by shutting it off at the disconnect box to the unit or unplugging the power source. 2. Open up the blower compartment of the furnace or air handler. Find the Full Load Amp (FLA) rating of the blower motor. If the motor is direct-drive these numbers can be difficult to read.
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.
Yes you can but we think its just better to know that it can be done whats involved with a simple speed change of your air blower for your furnace air conditioner or heat pump. Ryan from Environmental Heating & air of nc gives you the color codes and speed of those wires.
What causes a fuse to blow on a blower motor?
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.
Where is the blower motor resistor located on a car?
It’s located inside the dash, often on the opposite side of the steering wheel or inside the engine compartment on the firewall. A blower motor resistor or a blower motor control module is the part that controls the speed of the blower motor.
What can cause a / C blower motor to turn off?
My best guess would be that the blower motor may have bad bearings or other issues causing it to draw too much current, causing the overcurrent protection on the motor to kick in and shut the motor off.
How does a blower motor controller work on a car?
It’s really a simple concept: the blower motor controller pulses either the power or the ground circuit on and off depending on which fan setting you choose.
Why does the blower motor keep running after I Turn Off the car?
Why does the blower motor keep running after I turn off the car? If your car uses a blower motor controller, it can keep running the blower motor after you shut down the engine. Those used to be installed only on vehicles with automatic climate control with variable speed fans, but now they’re installed on many late model vehicles.
How does a blower motor reduce the speed of a fan?
In a vehicle equipped with a blower motor resistor, voltage is reduced by the value of the each resistor based on the position of the fan switch. The lower voltages result in lower fans speeds. The downside of blower motor resistors is that, in order to reduce voltage, a resistor converts the energy into heat.
What can I do about intermittent blower motor?
Try cleaning it by cycling the control from minimum to maximum rapidly a dozen times or so with the truck off. If that does not work you could take the HVAC controller out and try to get some spray electrical contact cleaner inside the rheostat and again swiping it a number of times.
How much does it cost to replace a blower motor?
See: how to check a fuse in a car. If a blower motor is bad, it will need to be replaced. The blower motor replacement costs from $320 to $650, depending on the car. In many cars it’s fairly easy; the blower motor is located behind the glove box and held by 3-4 screws.
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.
What to do if your blower motor gets stuck?
Blower motor gets stuck in a lat spot and will not turn. Once it’s gets going again it will be fine and work great. Will either replace it or, in the interim, will have to grease the shaft of the motor.
See: how to check a fuse in a car. If a blower motor is bad, it will need to be replaced. The blower motor replacement costs from $320 to $650, depending on the car. In many cars it’s fairly easy; the blower motor is located behind the glove box and held by 3-4 screws.
How to diagnose a blower motor problem?
Place two large straight pins in the plug of the blower motor but leave the blower motor plugged in. Place a voltmeter across the two pins. Turn on the ignition and turn the blower switch through each position.
How does a blower motor turn on the ground?
Normally you switch on a positive current to an electrical component to turn it on. The power passes through the part and then to ground to complete the circuit. With a blower, you essentially ‘turn on the ground’.
The blower motor operates only when the dash control is in the Defrost and Heat positions. It’s speed is directly controlled by the fan speed switch on the dash control panel. The Heater Core is located just to the left of the Blower Motor and has engine coolant circulating through it at all times while the engine is running.
How does a Hi vac lawn mower work?
The secret to the HI VAC mower’s cut is its unique blade and rolled deck edge that generates a large volume of air and creates suction. Electric key start for easy powering on every time, speed selection and cup holder are all conveniently located within easy reach (P2185020E).
Where is the blower on a Jeep Wrangler?
The blower motor is located directly behind and below the passenger vent (as shown) and pulls air directly from the cowl vent at all times while in operation. The blower motor operates only when the dash control is in the Defrost and Heat positions. It’s speed is directly controlled by the fan speed switch on the dash control panel.
Where is the electric key on a Hi vac lawn mower?
Electric key start for easy powering on every time, speed selection and cup holder are all conveniently located within easy reach (P2185020E). Rugged solid steel front axle and stamped steel mower deck provide long-lasting performance season after season.
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.
Is the blower motor on a Chevy Silverado working?
Blower Motor does not work on 1 and 2 speed chevy silverado – YouTube I had a Bad Relay. I got one here https://amzn.to/2PSr6fQ It seems the 88-94Trucks have a different system to control the speeds than the 96-00 OBS style Ch…
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 is the motor for the heater blower located?
The motor that turns the blower is called the blower motor. It is located in the dashboard, usually on the opposite side of the steering wheel or inside the engine compartment on the firewall. The blower speed can be adjusted in almost every modern car.
What’s the name of the motor that turns the heater?
When the heating or air conditioning in your car is turned on, the fan turns on and forces air out of the car’s vents. The motor that turns the blower is called the blower motor.