My Air Conditioner Keeps Running When Turned Off! The AC button has a light on the button that illuminates when the air conditioner is turned on. The most common reasons that AC blows warm air in car are leaks in the air cooling system, broken compressor, worn-out clutch or electrical wiring problems. Your car mechanic can utilize special car AC repair tools and diagnostics to determine whether or not your vehicle is running short of refrigerant. But you say you hear the blower working when running it at a reduced speed and just don’t get any air. 2005 GMC Sierra 1500 SLE Ext Cab 5.3L 4x4 - SOLD. Car AC Not Blowing Cold Air: A Bad Fuse. Most newer cars have a variable AC compressor, though, and in this case, no AC compressor clutch can fail. by Magnus SellénUpdated: February 8, 2021. This makes the AC compressor to spin and power the AC system. I think I have pinpointed it to a control head. Dust and debris collects and builds up within the filter which blocks air from coming through. Now, imagine that your car’s air conditioning system suddenly stops blowing cold air; how would you feel? The blower motor resistor or blower … Remove the cabinet cover and check that the motor … 2003 2500 HD with a Diesel. The Meaning of My AC Running but Not Blowing Air In addition, if your return vents were sized too small for your house’s air circulation requirements, that would likewise create low airflow. A clogged filter will restrict air flow into your home. https://www.wikihow.com/Diagnose-a-Non-Working-Air-Conditioning-in-a-Car RUN light blinks slowly (1.5 sec ON, 0.5 sec OFF) Airflow has stopped to prevent blowing out of cold air until the indoor heat exchanger has warmed up. I had a guy come in to my work this problem with a similar situation and it turned out to be an orifice tube or something along those lines. You’ll need an expert to evaluate your system, repair the cause of the leak and restore … Sometimes referred to as the PCB, this is an electronic control board that operates the fan motor and compressor circuits using relays mounted on the circuit board. It is like it freezes up after running above 55 MPH for about 35 minutes. Does that mean it needs to be replaced. Dealership is at a loss. Blower running but no (or little) air coming out, Re: Blower running but no (or little) air coming out, Blower not working at all and floor is wet under blower. I have good air circulation when truck is first ... SilveradoSierra.com - Chevy Truck Forum | Silverado Sierra GMC Truck Forums The only site focused on Silverado/Sierra trucks exclusively. Disconnecting the cycling switch and high pressure switch have no effect. The most common causes of broken air conditioning are leaks or compressor issues. This part aids the fan motor in circulating cold air. You'll want to check the … I hope you enjoy my content! However, refrigerant leaks can happen over time, and at $75-$100 a pound, you don’t want to wait to find the source of the leak. basicly your a/c system should unlock the compressor clutch when the temp reaches certain points. Most vehicles today have one multi-speed fan that blows air through a series of ducts and vents based on the driver’s selection in their climate control system. If you haven’t been regularly checking and changing your air filter, it’s most likely extremely clogged. If the motor is making a humming noise or turning very slowly, the capacitor may need to be replaced. If you want to know more, you can read our article Why should I replace my Cabin Air filter. Reply. Verify if this light turns on when you reach MAX A/C. If the pressure gets too low, it will also shut off the function of the AC compressor. When it is working properly, your cars' air conditioner is a wonderful thing. There could not only be damages to the AC compressor clutch; the compressor itself can also fail if you are unlucky. For this, we need a fan that can run instead of the wind at lower speeds. It might sound basic but if your AC is not blowing air, check to ensure that it’s plugged into the outlet correctly, and that the power cord is still intact. Some car compressors use a clutch inside the air compressor. I created this blog because I was tired of finding false information on the web while looking for repair information. 2003 2500 HD with a Diesel. The first thing to check with any issue related to the car's climate control or electronics is the fuse box. The Air condition control unit is often quite expensive, and it is recommended to check the other things first. (HOT KEEP program) Airflow is not blown out for 5 to 15 min. This may not be the correct answer but I get the same problem on my work truck (2005 freightliner) and the problem is that if the a/c is used when temp outside is cool the a/c core or whatever the radiator type thing is under the dash gets frozen over and will not let the air blow through the vents.... Again it might not be correct answer but it's a start.... i'd say that one of your "blend door" actuators is broken. Blower still does not work. Make sure the condenser and its environs are clean; otherwise it will have difficulty accessing air and could lead to the system overheating. Here’s the Fix By Michael Joseph. When it is not, which of course occurs on the most brutally hot day of the year, the A/C suddenly becomes a cruel joke, blowing warm, stale air into your vehicle. Its a 2001 GMC sierra 1500 HD crew 4x4. If it does not turn on, it is an indication that either the switch itself is malfunctioning or the AC circuit is not getting power. You do often have to replace the AC condenser at least every 10 years. The most common causes when car AC is not blowing cold air are an empty AC system, faulty air compressor, faulty AC pressure switch, and a clogged cabin filter. In case you feel that the air conditioner motor is not functioning, you can be ensured that the air conditioning system will not be blowing cold air. Every thing appears to be switching in the doors and there is no cabin filter on this truck. No mouse nest in the box. This means that you won’t only notice a lack of cold air, but probably a little more dust and an overall stuffiness. You can replace this clutch in many AC compressors or even remove shims for the clutch for it to work a little bit more. The condenser is installed in the front of the car, transferring heat away from the evaporator inside the car. If this actuator is faulty, your car might blow hot air out from the vents even if you require cold air. Anyone ever have the evaporator ice up? … Find the filter either behind your return grates (the metal slots in the ceiling where air gets sucked in) or in a slot before the furnace/air handler unit. Your AC system is filled with an ac refrigerant, making sure the whole system is working correctly. So after … If your air conditioner is running but not blowing any air and you have inspected the air filter and fan motor and found them okay, then you may have a problem with the control board. ANSWER: You’re low on freon If your air conditioner is running properly, you shouldn’t have to replace freon. If your air conditioner is blowing warm air, or just not working properly, it is best to schedule a service ASAP to maximize your comfort. If that is really true then the trouble would have to be with the vent doors somehow, it would seem to me. Car AC Not Blowing or Is Your Car AC Fan Not Working? Rotated all the PDC relays around, they have the same ID, other than ABS pump. Anyone ever have the evaporator ice up? Learn more: Has Your Air Conditioner’s Air Filter Betrayed You? It is recommended to check and clean the cabin air filter frequently. The problem may lie with a broken part. A dirty air filter could also freeze your evaporator coil. Here is a more detailed list of the most common causes of a car AC not blowing cold air. I have all my speeds and you can hear it running but not getting any thing out any of the vents. One potential issue that may cause your air conditioner to run but not blow cold air is a dirty air filter. Said he sold 4 this year. Airflow is not blown out when starting the HEATING opera- tion. The filter catches all the dust and impurities that enter the passenger compartment and can, therefore, become clogged over time. If you notice that your AC is working at higher speeds but not lower, there could definitely be a problem with the condenser fan. An AC not blowing sometimes is caused by a dirty condenser unit. Here is a more detailed list of the most common causes of a car AC not blowing cold air. Checked continuity of 40 amp blower fuse; it's okay. There are two main issues in the condenser that can lead to a car AC system blowing hot air. Have changed the orfice to help get rid of some of the water build up. If the AC compressor fails, you often have to flush the whole AC system afterward because there might be metal pieces everywhere. As the capacitor, present in the fan motor of the air conditioning system gets weak; it will be reducing the speed of the blower. Absolutely desperate, of course! Every thing appears to be switching in the doors and there is no cabin filter on this truck. nbs99 z71 325ci v8, stock 4wheel disc brakes, no cats, flow master classic 40 series, rhino line, custom fog lights, cb, bully dog tunner, 4:10 locker, airbag load leveling, 205,000miles. Having your car’s air conditioning go out suddenly can ruin your day fast. Your system’s air filter traps dust, dirt and other airborne pollutants to keep indoor air and internal cooling system components cleaner. I have all my speeds and you can hear it running but not getting any thing out any of the vents. The AC compressor pumps refrigerant around in the AC system for it to cool properly. This setup can look a little bit different, but the main function is the same. 9. Solution: Check your air filter. The cooling fan in the condenser is the first thing that you should look into while finding out the reason for car air conditioner not blowing cold air when idling. If the pressure gets too high – it will stop the AC compressor from cooling the system anymore because of safety reasons. If this fan fails, there might be a problem with the AC system at lower speeds. Rotated all the unmarked relays around in the junction box. Step 2: Verify that air is blowing. If the outside unit is running but no air is blowing inside, check that the returns aren't blocked, check that the filter is clean, and if that's not it, it's probably the fan or the blower motor (in my case, about a $500 repair) or the control board. Another common and easily remedied situation that sometimes results in a central air conditioner fan not working is a dirty, clogged air filter. Also, a clogged cabin air filter leads to a deterioration in the air conditioning system’s cooling. If this AC pressure is faulty, it can give the AC compressor faulty signals to stop – even if it shouldn’t, and this will cause your AC system not to function at all. So why is blowing warm air inside the car? Believe it or not, something as simple as a dirty filter could be what’s causing your air conditioner not to blow hard. If your filter is dirty, it should promptly be replaced. The serpentine belt powers the air compressor pulley, and when you activate the AC – the clutch is connecting the air compressor to the pulley. This kind of thing is usually caused by the resistors for the motor speed control or the thermo cutout opening up. The first is a blockage anywhere in the series of tubes in the condenser. Most older cars have wires for this, but newer cars have an electronic signal between these, which can fail. 06silverado_inny, you have a temp sensor problem. (2 to 5 min.) When this happens, your system has less air to condition. Improper running of condensing unit: The condensing unit in your aircon works to compress the refrigerants into its coil to keep the system cool but if it stops running smoothly then you may find your aircon blowing warm air. Vents seem to work good until i select defrost and then the flow goes away. You might not think your filter contributes to your AC not blowing cold air, but it does. Still have same problem. These different speeds are usually controlled through a set of resistors or a small computer module which is controlled by the fan switch. I am having the same problem. Although you can easily fix it by refilling the refrigerant level, it might happen that the compressor is broken since you did not use it in a long time. by 06SiLvErAdO_InNY » Oct 20 2011, 1:26am, problem work thing blower same anyone running coming thanks getting start used still think help sierra stock first, Users browsing this forum: No registered users and 9 guests, New here and searched but could not come up with an answer. it switches form hot to cold but just not enough air flow to to any thing. If this clutch is too worn, it may cause the AC compressor not to start at all. Imagine driving peacefully on a bright sunny morning, listening to your favorite music, and enjoying the scenery around you. I have good air circulation when truck is first started then it goes away. This often causes the AC condenser to start leaking refrigerant, which will cause the AC refrigerant to pour out. You don’t need to tolerate a stuffy, uncomfortable car … we covered that in class the other day. Why is my A/C blowing warm air? The AC system should always be leak checked before a refill. If the outlet and cord are fine, it could be an issue with your electrical panel. Anyone have any ideas? The air filter strains particles from the indoor air supply but when it fills to capacity, less air passes through. If the … A frozen evaporator coil. Tina, Depending on what kind of car you have it is possible that your compressor is ok and that is the standard cycle time. Fixing the AC could be as simple as recharging your car's AC refrigerant or repairing a refrigerant leak but may also require complex electrical climate control repair or slipping compressor clutch to get your air conditioning operating at top performance once again. The most common causes when car AC is not blowing cold air are an empty AC system, faulty air compressor, faulty AC pressure switch, and a clogged cabin filter. Thanks Blower running but no (or little) air coming out. If you leak in the AC system, the pressure will get lower and lower and finally stops working at all. Thanks. There are a variety of reasons why your car AC is not blowing cold air. If your car’s AC isn’t blowing air, it could be a problem with your car’s fan. Its a common reason for air conditioning units not to be blowing as cold of air as you would like. The condenser needs wind through it to remove the heat properly. Hi, I’m Magnus, the owner and the writer of Mechanic Base. Without getting too detailed, a dirty air filter makes it hard for air to enter into your AC system, which means you’ll be feeling low airflow. Your AC cools air by blowing it over the evaporator coil. For example, your thermostat may say 74 but the temperature won’t get below 80 degrees. 2Remove the door on the front part of the air-handler cabinet so that you can … The power output from the relays can be checked with a multi-meter, but this should only be attempted by a qualified person. Then if i go to vents it is gone. If this fails, it may send the wrong signal to the blend door actuator, and this may cause it to blow hot air instead of cold. it switches form hot to cold but just not enough air flow to to any thing. The AC system is also leaking very slowly through hoses and other places. Not blowing - New here and searched but could not come up with an answer. #2: Frozen evaporator coil. This refrigerant system is of high pressure, and it can reach 15 bars when the car is running. It is possible that there is dirt or moisture that has built up in your car’s air conditioning unit. I have been working with cars for 10 years, specialized in diagnostics and troubleshooting. The last cause on this list is a faulty heat controller. It can be cleaned out to help resolve the problem. As you might understand, it won’t pass any wind through it at lower speeds. Any degree of blockage in the system can lead to the condenser not being able to execute its principal function. This is very slow, though, and you can expect to refill it every 6-7 years. If your air is blowing cool but not cold, the problem could be a clogged filter, cooling fan problem, radiator trouble, or it could simply be that you need to recharge your AC. For the AC system to work properly, it needs this pressure and a specific amount of refrigerant. The main issues that occur with the car’s air conditioning system are due to poor maintenance. When the car ac is not blowing air from vents it is a sign of a faulty blower fan or air duct blockage. We … This obstruction in the running of condensing unit can be due to easy reason like tripping of circuit breaker and complicated like its bad condition. Air condition is blowing hot air now. It does it no matter if you are running heat or A/C. There are two AC pressure switches in your car that monitor the high-pressure side and the low-pressure side of the air condition system for safety reasons. Problem #2: Frozen evaporator coil. Why should I replace my Cabin Air filter. Each of these problems has its own … When you turn the heat controller on the AC control unit, there needs to be something that controls the heat inside the car. Have replaced the actuators, and the main controller. Hot liquid refrigerant stays hot. The condenser unit, which is usually located outside, is exposed to dirt, soot, debris, tree branches, twigs, leaves and all types of weather. The task of cleaning a … Apart from this, the speed of the AC motor will be slower. 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