Blower motor works sometimes
I'm having trouble with the AC blower motor going on/off. My car shop can't find the problem. Can you tell me what to tell them in order to get this fixed?
Experienced mechanics share their insights in answering this question :
Your car has an automatic temperature control system and it sends signals out to the blower controller in the evaporator housing in the engine compartment. The blower controller is the most common failure along with the blower motor. The blower motor draws too many amps and causes the controller to turn off and on. This burns out the controller and it will need to be replaced with the new blower motor.
How to Identify and Fix Common car Problems ?
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The fan switch may be at fault, but a more likely reason is that a blower motor resistor that controls the voltage going to the blower has packed it in, resulting in only one speed remaining operable – usually the highest speed.
When the fan runs intermittently, it could be one of two problems. First, the motor could be overheating, which causes it to cut out. Alternatively, a loose wire, connection, or a short in the motor windings could be the culprit. Any electrical-related problems should only be addressed by a professional.
Problems include dirty filters, broken wires, poor voltage supply and faulty limit switch or capacitor. You can test your limit switch with a multimeter, and clean the blower motor`s wire coils. If this doesn`t work, you may need to replace your furnace blower motor.
Your AC unit turning on and off repeatedly is one of the most common AC problems homeowners face. It can be caused by dirty, damaged, failing components or electrical and mechanical factors. If your AC unit keeps turning on and off repeatedly, then it`s probably experiencing short cycling.
A furnace cycling on and off repeatedly can be caused by various reasons, from dirty filters and obstructions in ducts and registers to incorrect thermostat settings and faulty limit switches.
A lot of different factors, of varying seriousness, can result in short cycling. The most basic issue to resolve is a very dirty air filter. If your air filter is too dirty, then the AC can actually start to overheat due to the excess strain put on it. Then, it will shut itself down in an act of self-preservation.
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.
AC Works Intermittently: When the air goes from cool to warm to cool again, you`re experiencing intermittent problems. This is often due to a clog in the system, a failed compressor or compressor clutch, a faulty condenser fan, a clog in the system, or the actuator directing airflow has failed.
The blower is supposed to last the entire lifetime of your car. However, situations vary and some climates require the fan to be used too often. Many car owners find themselves having to replace the blower after five years. The quality of the motor used to power the blower matters.
Clogged Intake Filters
Without enough air, compressors will stall, and yours may hum when you try to restart it. To check and see if your air filter is the cause of your air compressor humming, unscrew and remove it, then restart your machine. If it works, you need to clean your filter.
Lack of maintenance: This is probably the most common reason that causes condenser fan motors to overheat and shut off. Proper and regular lubrication of the fan motor is necessary for the motor to run smoothly. Periodically making sure that there`s no debris or dust in or around the fan motor is also a good idea.
Weak or Absent Airflow
Weak airflow or total lack of it is the most obvious sign of a bad blower motor. The problem could be due to a clogged blower from accumulated dust or debris. It could also be due to leaky air ducts or a bad capacitor.
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.
The blower motor is an important component of your air-conditioner. If it isn`t working properly, it can significantly affect the comfort level and air quality in your home.
Your car`s blower motor is not only necessary for the operation of your air conditioner. Without a functioning blower motor your engine runs the risk of overheating.
If your air conditioner only stays on for a few minutes at a time and shuts off before it has a chance to cool your home, this is called short-cycling. The issue is relativity common and can have a range of causes, from a clogged air filter to an oversized system.
Most air conditioning units are equipped with a reset button. These buttons tend to be red and quite small. If you`re having a tough time finding it, consult your owner`s manual.
The ECM Motor
In the simplest terms, an ECM motor lowers the total electrical consumption of an AC or furnace and helps to maintain proper air flow through the system. ECM motors contain a microprocessor, which is the key component of what makes them able to provide higher efficiency.
There are a number of things that can go wrong with your heating system, but if the air stops blowing altogether and the same is true on cold air settings, a blower motor replacement is likely in order. The good news is that it`s a fairly straight forward repair.
A fan limit switch is a component of a furnace system that determines when the furnace blower assembly for hot air turns on and off. Essentially, this means that it determines when the hot air should be blown through your ventilation system.
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.
Relevant Questions and Answers :
the most relevant questions and answers related to your specific issue
My car ac a year ago stopped working on settings 123 only works on 4 I did the research so I do know it is the blower motor an ha
ANSWER : In your application, there is a replaceable blower motor resistor block. The resistor block permits multi-speed operation of the fan. If some fan speed settings work, but not others, the first thing to do is test the resistor block with a volt ohmmeter. If you desire testing, and replacement, as needed, please request a blower motor/resistor block diagnostic and the responding certified mechanic will get this taken care of for you.
With regard to the A/C system, if gauge pressures (high and low) are normal when the system does operate, there are really only two principle possibilities for intermittent operation. One is circulating moisture in the system (due to a saturated dryer) which periodically freezes (and thaws) at the expansion valve and the other is a failure in the A/C control system, that is the clutch, sensors, and other electronics that control the compressor cycling. The cause of the problem can be readily found if you request an A/C system diagnostic. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.
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Front A/C blower motor working incorrectly.
ANSWER : One sure way to rule out the blower motor itself would be to observe voltage while the issue is happening. If the voltage being fed to the blower motor fluctuates, the problem is on the control side of the circuit and possibly the resistor. Hire one of our mobile experts to swing by and test the electrical system and track down this bug.
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Blower moter works intermittently, sometimes it blows air tand sometimes I get nothing, motor or resistor?
ANSWER : Sometimes the blower will not turn due to an open circuit in the blower motor brushes. When you are experiencing the problem where the motor does not come on then just lightly tap on the blower motor in the left side bottom of the dash. If motor starts turning then you know the motor is bad and needs replaced. Have a mechanic like one from YourMechanic to come and do further testing or replace the blower motor.
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Fan blower motor not working replaced resistor and blower motor but I don’t know we’re the fuse or relay is located
ANSWER : The fuse and relay is in the power distribution center which is mounted under the hood on the left side of the engine compartment. Remove the top cover and look on the under side of the cover. You will see a diagram showing the position and name of each fuse and or relay. Keep in mind to make sure you are correctly oriented with the position of the fuse block. It can be confusing at times.
In addition to the fan motor, relay, fuse, and blower resistor, the A/C heater controls the fan speed selection. These are known to fail on Chrysler products. A scanner capable of communicating with the climate control system is necessary to diagnose this system. To avoid any unnecessary repairs, have a certified technician, like one from YourMechanic, diagnose your heating & A/C issue firsthand.
Good luck!
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Car starting sometimes, sometimes have to jump, speedometer and tach working but all other gauges not working 2003 GMC Yukon
ANSWER : Hi there – check fuses first, but it sounds like you might have a problem with your digital dash, and possibly a wiring issue that is draining your battery overnight. The lack of gauge function is is a high failure rate circuit board issue, but there are rebuilder service companies out there that specialize in this work. The battery drain issue maybe be a different problem, but can be tracked down as well. This problem can be diagnosed by connecting an ammeter to the positive (red) battery cable, observe the current drain (likely less than 1 amp), then, one at a time, remove each fuse, check to see if the current drain has dropped to near 0, then reinsert the fuse. This process should identify the faulty circuit in most cases. The specific components on that circuit can then be checked for current drain problems. A professional mechanic, like YourMechanic, can come to your location, and perform this procedure for you, and replace/repair the failing component.
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Blower Motor only working on highest speed.
ANSWER : You mentioned that you started to smell something. This may be a sign that the blower controller or the resistor was burnt out when it was hooked up wrong. You should try replacing the blower controlling resistor that you hooked up wrong. But like you mentioned, it could also be a fuse problem that has shorted. If you would like to have this looked at, have a certified technician, like one from YourMechanic inspect the wiring and determine what should be done.
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My AC does not always work. If I fiddle with the blower knob I can ususally get it to work on the lowest setting.
ANSWER : Hi There,
It sounds like you may have a faulty blower motor resistor. The highest speed setting may still work because in most cars in the highest fan speed settings the current bypasses the blower motor resistor. In some cars, if the resistor is failed, the fan may stop working completely. Another reason a blower motor resistor may fail is when the blower motor has a mechanical problem or when a foreign object jams the blower motor fan blade and prevents it from spinning freely. This leads to increased current through the resistor and causes it to overheat and fail. I would suggest having an expert from YourMechanic come to your location to diagnose your system to determine what may be causing the fan not to work properly.
It sounds like you may have a faulty blower motor resistor. The highest speed setting may still work because in most cars in the highest fan speed settings the current bypasses the blower motor resistor. In some cars, if the resistor is failed, the fan may stop working completely. Another reason a blower motor resistor may fail is when the blower motor has a mechanical problem or when a foreign object jams the blower motor fan blade and prevents it from spinning freely. This leads to increased current through the resistor and causes it to overheat and fail. I would suggest having an expert from YourMechanic come to your location to diagnose your system to determine what may be causing the fan not to work properly.
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An inconsistent starter motor that occasionally works perfectly now will not work. Then engine will not crank at all.
ANSWER : Hi there. It is possible for the starter to fail. But before replacing the starter, make sure that the battery cables are tight and clean. Then check the starter relay and make sure that the relay is clicking. If the relay is not clicking, then check for power to the relay. If there is power to the relay but there is no click, then the starter relay would need to be replaced. If there is no power to the relay, then either the wiring from the relay to the ignition switch has a break in it or the ignition switch is failing. If there is power to the relay and power to the starter motor, then the starter motor needs replaced. If you need further assistance with your no start issue, then seek out a professional, such as one from Your Mechanic, to help you.
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