But if the system is low on refrigerant, the clutch will never engage. Belt squealing when AC starts. Not sure what would cause the pulley to do this. Being the clutch turns by hand, the cluch assembly, which will include a pulley, a clutch plate, and a coil, can be replaced, without replacing the entire compressor. Changing the compressor clutch could be the only solution in this case. Both the pulley and the clutch should be spinning. In some cases, a fuse would be blown or a breaker would be tripped. At least the pulley will rotate. Some cars (not Kia) can have a compressor bypass pulley installed & forget the compressor. With engine running and the AC set to MAX, use a digital voltmeter to check for battery voltage and good ground at the connector. Will be getting a new pulley bearing for it and will re-install once the weather starts warming up again. This is a full explanation of how the system works. (When done properly) does a turbocharger improve or hinder gas mileage? When the clutch is engaged, the pulley … Join Yahoo Answers and get 100 points today. A bad AC compressor clutch needs immediate fixing. The low pressure tubing is always a larger diameter than the high pressure line. Turn the air conditioning controls to MAX AC and start the engine. That saves a lot of time because you don’t have to refer back to the component locator or circuit locations. The air compressor pulley rotates at all times when the engine of the car is working. Are the tires I bought good for the time being? Just bought a 2000 Jeep Cherokee Sport cheap with that same problem. In other vehicles the power flows through the air conditioning switch to the fuse and from the fuse through the low pressure and evaporator temperature sensor to the clutch coil. Pulley & mount about $75 on internet and a couple local mechanic to remove old & install new pulley. Doing so will force the compressor to run with inadequate oil and can destroy the compressor. The clutch disc is splined to the  compressor shaft. If the fuse is good, disconnect the electrical connector from the compressor clutch coil. All that tells you is that there is some refrigerant in the system. See if you can find a belt that will fit that just operates the power steering pump. Higher Temperatures Than Normal In The Cabin. To tell the a/c is on. If you’re tracking down a wiring issue, Eautorepair.net is the better choice. Try turning the pulley with the car shut off. I bought a new one and installed it, but it isn't turning the compressor when engaged. IF the pulley will not spin, then the bearing is shot at the very least. If you’re not getting battery voltage, pull the compressor clutch relay and check for power and ground on the relay control coil terminals in the socket. While AC pump noise is totally normal for your car’s air conditioner, hissing at any other point may give you reason to visit your mechanic, just like a buzzing noise. I pulled the belt off and gave each a spin. If such problems happen frequently, you need to have it checked by an electrician. The clutch is the outward most plate on the compressor, pulley is in the middle, and the coil is nearest to the compressor. An AC bypass pulley is a free spinning pulley used to replace the AC compressor on an automotive engine. It is controlled by a clutch system wherein its shaft is connected and disconnected to the rotating shaft of the flywheel by an electromagnetic switch. The noise is the clutch slipping against the pulley because the compressor is very hard to turn. However, I’ve been around long enough to know you’ll try to recharge it against my advice. One of the first signs which is really to recognize … Until today the belt and pulley would still spin with the A/C on. But chances are some of it will still reach the orifice tube and flow into the evaporator coil. The a/c pump has seized but it would a little rare for the clutch to seize as well. When she got home, I quickly realized the problem: the AC rotor pulley wasn't spinning and the serpentine belt was just dragging across it! Turn the AC to MAX to start the radiator fans. However, once installed the vehicle will no longer have air conditioning. Static low side pressure won’t give you any idea of system charge. DIY kits come with a low pressure side gauge and they’re designed to provide a static pressure (engine not running or AC off) and a running pressure. After buying new belts I realized the belt didn't just break because it was old, the air conditioning compressor pulley won't spin at all when I try to spin it with my hand, making me believe that the belt was being dragged around a pulley that wouldn't spin, forcing it to snap. Might as well leave the compressor in, It acts like an Idler pulley when not in use. Reply to Thre You cold likely adjust that belt to stop the noise. Pricing: ---Eautorepair.net--- 1 month subscription $19.95 per vehicle 1-year subscription $29.95 per vehicle 4-year subscription $44.95 per vehicle ---Alldatadiy.com--- 1-year $29.95 subscription: additional vehicles $19/95 each 5-year $49.95 subscription: additional vehicles $34.95 each Which one should YOU choose? DIY recharging kits tell you to recharge through the low pressure port while the compressor is engaged. On a '99 Corolla, if the left parking light is out, but the left turn signal works, is it just a bulb, or should I replace the assembly. The idler pulley should spin whenever the car is running if the belt is properly tensioned. Let us now learn how to manually engage AC compressor clutch. Then the system should be fully evacuated to remove all air before recharging. What could be wrong with my air conditioning compressor? Some DIYers then hotwire the low pressure switch to force the compressor clutch to engage while they recharge. During startup the air conditioning/power steering belt has been squealing and screeching. I have a 96 mazda protege. In a computer controlled system, the compressor clutch relay is grounded by the computer. If your vehicle is an orifice tube system, the refrigerant gas will flow through one of the open compressor reed valves and into the condenser coil. Then look at the front of the compressor clutch. You may get it to accept a charge, but you may have already damaged the compressor before the system reaches full charge. However, Alldatadiy.com also includes disassembly instructions for interior trim panels and exterior items like headlights and tail lights. Not sure on the 2.5's. Start the engine and let it warm up. Wiring varies by make, model, and year. It is an ominous sign when the clutch engages but the compressor does not spin. BAD MOVE. Car makers use an electro-magnetic clutch to engage and disengage the air conditioning compressor. Now look at the pulley of the air conditioner compressor. AC compressor clutches receive power in a number of ways. That would be cheaper but you get what you pay for. That means the clutch has properly engaged with the pulley. GOP lawmaker's death brings home reality of COVID-19, Jennifer Lopez responds to claims about her looks, Brady, Brees share special moment after playoff game, What to expect from Biden on student loans, Man lived inside airport for 3 months before detection, Trump chided Comey in newly revealed letter draft, Michelle Obama shows off her natural curls in birthday selfie, Mahomes scare offers stark reminder to Chiefs, A 'Major' celebration for Biden's history-making pooch, 'You are outnumbered': Stunning new Capitol video, Rebekah Jones in jail after Florida issues warrant. There is a way to add more refrigerant without hot wiring the low pressure switch and running the compressor. In both of these scenarios, you’d start the diagnosis by checking the compressor clutch fuse. Be warned that I take no responsibility for any damage you cause by using this technique. A delay can cause serious damage to the air conditioning system and the engine. The pulley and clutch can spin by hand. Losing the belt while commuting is far more expensive than simply replacing it. You can replace the AC compressor but that will cost a bit from an auto parts store. Then start adding refrigerant. However, to read the high side pressure, you’ll need a manifold gauge set. If you have an expansion valve system, the blower fan will prevent the sensing tube from shutting down the expansion valve while you try to add refrigerant. if the ac compressor pulley is not turning could that be related to the alternator going out 1 Answer. But on my 4.2, to pull the a/c compressor you will need an idler pulley to replace the a/c clutch pulley because of the thermostat housing. The AC compressor pulley or compressor clutch has a bearing inside of it that enables the pulley to spin without the clutch being engaged. NEVER! 50 MPH air conditioning os just fine. Try turning the pulley with the car shut off. A static pressure taken on the high side is a slightly better indicator of system charge because the high side is much more responsive to ambient temperature than the low side. But 1 ounce of refrigerant will provide a 50-psi reading the same as a full system. I turned it on high thinking maybe the light is burnt out, but nothing checked the compressor to see if maybe spinning regardless of the light and nope.nothing. But even then, it will only tell you if there’s some refrigerant in the system. It won’t be under pressure since the compressor isn’t running. If the clutch doesn’t engage, the problem could be a blown fuse, an open in the wire to the clutch coil, a bad clutch coil, a poor ground, or a low pressure lockout. If so, try the troubleshooting techniques described here. Turn the key to the RUN position and turn the blower fan to HI. This prevents from engaging the whole mechanism when the AC is OFF. After reading, go to this post to learn how to diagnose a compressor clutch problem. Can I cover the holes with tape to keep it working properly? When power energizes the clutch coil, the magnetic field pulls the clutch in towards the pulley. It is slipping ever so slightly, but if the belt has 100K on it then replacing it is wise as it is due. Period. That’s why car makers install a low pressure switch–to prevent the compressor from running if the system is low on refrigerant. Stand in front of the AC compressor at the front of the engine. Then look at the front of the compressor clutch. The part you see on the outer side of the pulley spins or stays still with the compressor, but the pulley itself will still be spinning even when the … The center part on the pulley of the A/C compressor will not spin when you have the air conditioner off or if there is a problem. If the clutch doesn’t engage, the air conditioning compressor can’t pump refrigerant. Could try to find one in a bone-yard. So you have to refer to the factory legends to learn the identification symbols and then refer back to circuit diagrams to find the splice and ground locations. The bearing in the clutch pulley is probably seized. After a few minutes, you may be able to build up enough pressure to close the low pressure switch. At that point you’re running the compressor with little to no oil. They include wiring diagrams and technical service bulletins. IF the pulley DOES spin but the clutch won't move (with the pliers) then you're looking at a new compressor. If you’re here, chances are you’ve tried to recharge your AC system and found a compressor clutch not engaging issue. Not really. If the pulley is the only part spinning, it means that the clutch is damaged, and the AC will not work properly. In some vehicles the compressor clutch relay is turned on and off by the low pressure switch and the evaporator temperature sensor. So the AC pulley is actually pressed onto the compressor's body and is always connected to the AC shaft through something called a hub plate with 6 rubber dampeners. I listened to the noise with a mechanics stethoscope and determined that the noise was either coming from the air conditioning compressor pulley bearing or the belt tensioner. So try starting the engine and checking the compressor. The center part (the clutch) should be engaged and should be spining along with the pulley. The noise was definitely a bearing sound. Still have questions? When the AC compressor goes bad in a vehicle, a consumer often will choose to install an AC bypass pulley. Eautorepair.net redraws factory wiring diagrams in color and includes the component, splice and ground locations right in their diagrams. If it worked well yesterday, unless the compressor grenades, it will slowly deteriorate if it is in fact failing. First, turn ON the AC and fan to the maximum. I would think that a good compressor should turn also. If you look at the center of the pulley, when the a/c is off, the central portion of the pulley should be stationary. It's only about 1 mile to the mechanic. Air conditioning compressors need a constant supply of oil to prevent catastrophic failure, and it’s the refrigerant that carries the oil through the system. One more thing, if I determine I can't fix this, could the car be driven without the air conditioning and power steering belt? With the blower fan running, any liquid that enters the evaporator will boil and turn back into a gas. If the plate doesn't want to turn but the pulley is still turning with the belt than you could have a few things going on. Best Regards, Wayne Get the BEST auto repair information Alldatadiy.com and Eautorepair.net are professional-grade shop manuals—period. The only thing a kit gauge can tell you is that your system is completely empty if you attach the gauge and get a reading of 0-psi. In most cases, their diagrams are right from the factory manuals. Alldatadiy.com, on the other hand, uses the factory diagrams. If an air conditioning system is so low on refrigerant that it can’t engage the compressor clutch, it’s really too low to be recharged with a DIY kit. Both the pulley and the clutch should be spinning. In order for the computer to provide ground, it must receive a good signal from the low pressure switch, high pressure switch, and evaporator temperature sensor. Turning off your car will cause the Freon to move from the high-pressure part of your AC compressor down to the side with lower pressure to equalize out. NEVER try to bypass the low pressure switch. In that case, the PCM would see that the refrigerant pressures are within bounds and the PCM would provide a ground connection to the control coil side of the AC compressor clutch relay. Both the pulley and the clutch should be spinning. Cool Automotive Products and Tool Recommendations, go to this post to learn how to diagnose a compressor clutch, Read AUTO REPAIR ARTICLES sorted by topic, 8 Reasons Your Car Might Not Be Performing Well (And How to Fix Them), Custom Wordpress Website created by Wizzy Wig Web Design, Minneapolis MN. Some car makers trigger the relay control coil ground through the PCM or ECM. The face of a compressor is comprised of a clutch, coil and pulley. The middle pulley is bypassed by running the belt straight line from the upper rear serpentine idler straight to the power steering pulley, then over the water pump (the smooth pulley powered by the back side of the belt) and down to the engine drive pulley (harmonic balancer), bypassing the AC compressor… Turn the air conditioning controls to MAX AC and start the engine. Maybe you can just go without the a/c for now. This car is a 89 isuzu imark. The compressor does not turn with the motor running, the belt just slips around the pulley and is not burning as you would think. I havent used a/c in years so i just wanted to try turning it on and the light on the button doesn't come on anymore. AC bypass pulleys are much cheaper than a new AC compressor. When the air conditioning is turned on inside the vehicle the compressor clutch will engage and begin to spin with all of the other pulleys. You must log in or register to reply here. Moisture reacts with the refrigerant and oil to cause acid and sludge that can destroy the system. The pulley should turn all the time, with the belt, but the compressor only turns internally when the clutch engages. Get your answers by asking now. See the link below for some pictures. … The pressures developed will slowly fall off, leading to not so cold air. The leak is large and should be repaired, because there’s probably air and moisture in the system. Plus, the DIY kit fitting will only attach to the low pressure port. The first and also the most necessary thing to do when an AC compressor does not work is to ensure that this unit is still receiving power. If you need to dig into your doors, dash or console, Alldatadiy.com is the better choice because Eautorepair.net doesn’t any interior or exterior trim or body part removal. Connect the recharging kit to the low pressure (suction) port. The a/c pump has seized but it would a little rare for the clutch to seize as well. As some of you know, these cars do not have an AC clutch, instead the AC compressor is always spinning and is engaged on demand by the ECU through the means of a solenoid. I have an old loud muffler that has holes in it and is rusted? If this technique doesn’t work, take it to a shop. As the clutch disc pulls in towards the pulley, the pulley provides the rotating power to operate the compressor. But why would the compressor just now be seizing up? This may require special tools, and compressor removal, and has to be done properly, or the compressor will be damaged. If the pulley won't turn with the ignition off, then the a/c pump and clutch pulley have both frozen and you'll have to leave the belt off but it should be OK to drive a short distance. So start your diagnosis by determining if the compressor clutch works. The compressor clutch air gap is critical to the AC compressor clutch engaging. Move it away from moving parts so you can safely check for power and ground. Easy fix in my Jeep not sure about a Protege though. An AC clutch compressor is a type of compressor that derives its power from the car engine’s flywheel. Also, the air conditioning stopped working about a month ago (I thought the freon just needed recharged, but I could've been wrong). Compressors have an external pulley that is connected to the drive belt, and an internal pulley that is linked to the compressor’s input shaft (compressor works by its rotation). just a quick update on this - it is definitely the tensioner pulley for the AC belt - it is shot - crunchy sounding and does not spin smoothly. This is why I was thinking that there may be some kind of blockage. Or, the relay can be operated by the PCM which has interpreted the condition of the low and high pressure sensors. Do NOT hot wire the low pressure switch. I haven’t had a chance to put a wrench on the compressor bolt that holds the clutch to see if the compressor is frozen but will keep you posted. Replace belt or compressor/pulley issue? Then look at the front of the compressor clutch. I've checked the fuses and there still good. Ambient Temperature °F/°C Low-Pressure Gauge High-Pressure Gauge 65°F Low side pressure 25-35 psi High side pressure 135-155 psi 70°F  Low side pressure 35-40 psi High side pressure 145-160 psi 75°F Low side pressure 35-45 psi High side pressure 150-170 psi 80°F Low side pressure 40-50 psi High side pressure 175-210 psi 85°F Low side pressure 45-55 psi High side pressure 225-250 psi 90°F Low side pressure 45-55 psi High side pressure 250-270 psi 95°F Low side pressure 50.55 psi High side pressure 275.300 psi 100°F Low side pressure 50-55 psi High side pressure 315-325 psi 105°F Low side pressure 50-55 psi High side pressure 330-335 psi 110°F Low side pressure 50.55 psi High side pressure 340.345 psi Ambient temp is the outside atmospheric temperature.