How To Test Ac Clutch Cycling Switch

However, now when I turn on the AC (normal or max) the compressor seems to kick in only for about 2 seconds then turns off. I do not know how either of them look and where exactly to find them. Replace or restore your worn out air conditioning with this pressure cycling switch. Ford Cars and Trucks 1980 thru 93. Typically clutch cycling for temperature control is used in conjunction with a fixed orifice tube instead of an expansion valve. With the AC compressor running it should read ~40psi. Pressure switches are commonly tripped by occurrences like clogged vents or hoses, dirty filters or condenser coils. Figure out what's wrong with your car's A/C and fix the problem yourself, all for less than the diagnosis alone would cost at most auto repair shops. The ECM will cycle the clutch several times a minute to keep both passenger compartment and evaporator at the correct. Finish: White. Although most cars can blow air at temperatures as low as 60 degrees, the temperatures inside the evaporator core can get cold enough to completely freeze the entire core. Inspect the motor coupler. I've determined that whatever provides the grounding path for the clutch relay does not do it. ; Based on a signal from the thermostat, by means of an inter connecting electrical system, the electromagnetic clutch on the compressor engages. This switch turns the compressor on and off to keep the evaporator temperature at about 32 to 45 degrees F. The PCM supplies a ground to do this. It has finally gotten hot and it seems we are fully into air conditioning season (let’s hope it stays fo a while). A full cycle of AC uses the entire wave of the south and north magnets. 2 - IF the hi/lo pressure switch only effects the control signal (coil side) of the compressor relay and is NOT in series with the clutch itself then my contact shorting test above proved that the compressor clutch is wide-open and thus bad. this is a signal that goes from the hvac control module to the switch then to the PCM input. No CHECK and REPAIR the refrigerant system for leaks or low charge or incorrect A/C compressor clutch air gap. Do you have the draws ECM to AC clutch ralay, and instruction how to test it, Some thing is around ECM, AC realy, and AC clutdh switch. Air Conditioning System: Electrical For this issue of Fiero Focus, we're going to continue our electrical circuit path discussion topic; this time of the Air Conditioning (A/C) system. Search With Vehicle An air conditioner clutch cycling switch measures pressure to detect the flow of refrigerant in your system by sitting in the low pressure side of your A/C. For information on the specific function of the A/C cycling switch, refer to the Workshop Manual Section 412-00 Climate Control System. Check ac clutch fuse then check for voltage at the connector to the clutch. Had AC friend to check pressures and amount of coolant and all normal. What year and model and engine? Is the compressor getting voltage?. Noticed my AC wasn't blowing cold (this was the first time I had it on this season), so I pulled over and saw that the clutch is not engaging. Measure the voltage between the A/C cycling switch C139 pin 1, circuit 441 (RD/YE) and ground. The switch should open (stop compressor) at about 23# and close (start compressor) at about 43#. Upon reaching the set cabin temperature, the clutch is again disengaged and this cycle goes on till you turn off the AC. I took it to Goodyear and they tested it. you're going to have to test for power at the power side of the ac clutch relay. Both times were at initial startup in the morning. 1998 Ford Contour Fuse Box Map. Replace or restore your worn out air conditioning with this pressure cycling switch. The 2000 Xterra's Air Conditioning is sometimes cool but may not work other times. A full cooling cycle occurs from the time that the unit kicks on to the time that the temperature you set at the thermostat is reached and the unit kicks back off again. Make sure you have the fan turned on medium. Doing so saves your compressor from damage. If it's not, you may need to fix the cooling fans on your radiator or replace the cabin air filter. Introduction: This bulletin announces the availability of a new Air Conditioning compressor / clutch assembly to address customer concerns of the system not operating. The best part is, our Ford Expedition A/C Clutch Cycle Switch products start from as little as $11. It's not the fact that your air conditioning system is cycling that is a problem, but the frequency that indicates problems. Have checked at fuse panel, good there, not getting any voltage at any points in engine compartment, (pressure switch, clutch, etc. Although most cars can blow air at temperatures as low as 60 degrees, the temperatures inside the evaporator core can get cold enough to completely freeze the entire core. This is done by using a diode or a one-way check valve. The reason I ask about not using the gauges to check the switch is because its about 27 degrees out. If the vacuum reading holds you dont have a leak in the system, then the system is recharged to spec. on my vehicles, including my E-420, a full can of R134 will give enough pressure on the low side to start cycling the compressor even when vitually empty of R134. Your truck has a clutch cycling switch which is mounted in the side of the receiver/dryer. main power for the a/c clutch must be switched through a relay because of the high current load so it may be switched in the heater control panel or the relay is inside the truck somewhere but wherever they put it, its most likely the relay switch that is. Following are example prices for Car AC Clutch Cycling Switch Replacement. 5) OK, the Air Conditioning Compressor Clutch will not engage, so lets figure out why not. There is a high side switch too but I think it's mounted on the compressor itself and haven't heard of it failing much. Im my case, downstream. Check the operation of the climate control and the A/C button. I did that to mine while I was replacing all the o-rings in the system. Don't have my multi-meter with me to check signal at compressor clutch connection. Seeing as how it's reading MUCH higher than that, I don't think the compressor is engaging. I decided not to have it reapied there and they wouldn't tell me exactly what needed to be done. Since your post does not state the MY, I am going to surmise that one wire is the clutch power and the other is the field coil ground. --Fuses OK-. For instance, a leak in the system allows the refrigerant to escape. Four Seasons 35751 A/C Clutch Cycle Pressure Switch for Air Conditioning hl. Unable to cool the car Check your in-box to get. This could be either the control module, or the clutch cycle (thermostat) switch. so I looked for fuses and what not but that wasnt the problem. It may be doing what it is supposed to do in this weather and it may be cycling when you are driving. One of those diagnostics is units cycling or locking out on pressure switches. Failed AC clutch. If you are troubleshooting your system, you may also want to test the pressure switch itself. Jumping the pressure cycling switch is common practice on domestic CCOT systems, but the Civic is temperature cycled and fully controlled by the ECM. My blower is working correctly, by blue AC switch lights when depressed, but compressor clutch is not engaging, nor is the idle advancing. at idle with truck off (after a cold soak) and ac/ off the pressures should be about the same as the surrounding air. Air conditioner system discharged. You could bypass the cycling switch for just a few seconds to see if that engages the clutch or not. Note also that three of the switches would be cycled frequently during normal use: the ignition switch, the AC mode switch and the clutch pressure-cycling switch. The Jaguar cooled as good or better than the other cars I currently own, all of which have original factory 134a AC systems. The diode is only to hold down electrical spikes. A/C Clutch Cycle Switch - ([A/C Clutch Cycle Switch] TO ACCUM, BLACK; Quantity needed per vehicle: 1). Car makers use an electro-magnetic clutch to. But it's negative , not positive, Then the AC clutch engaged to AC compressuror. Pressure switches are commonly tripped by occurrences like clogged vents or hoses, dirty filters or condenser coils. If it does, then the PCM is not happy about something. Electric Air Conditioning Fan. Today I sunk $10 into a new AC Vbelt and hot wired the clutch. This will usually happen when a condenser fan fails. How do you bypass the ac pressure switch? I need to put in some freon and the pressure is so low that the pressure switch won't let the compressor kick in. The other switch is the A/C Cycle switch and that is located on the tube coming from the middle of the engine bay behind the firewall. You disconnect the wire connector at the compressor and put a lead to the battery to see if the clutch engages. Function of the ac compressor Cut-off switch in a vehicle. Symptoms of a Bad or Failing AC Clutch Cycling Switch. The APAds system: Prevents rapid cycling of the compressor clutch due to high- or low-pressure conditions. If the clutch engages, the problem is the clutch power supply (relay, fuse, wiring, switch or control module). It sounds like it may have a faulty clutch cycling pressure switch that's screwed into or near the accumalator/dryer. Check out free battery charging and engine diagnostic testing while you are in store. Today I sunk $10 into a new AC Vbelt and hot wired the clutch. Tighten or replace belt. If the clutch does not engage, use a voltmeter to check for 12 to 14 volts at the pressure switch. If you don't add more r-134 to the system and allow the AC compressor to cycle you will destroy the compressor. A/C-HEATER SYSTEM 1995 Chevrolet Tahoe 1995 AIR CONDITIONING & HEAT General Motors Corp. Testing and replacing the AC Clutch Cycling Switch on my second gen Cummins, went from blowing warm/ambient air to blowing cold! If your AC clutch isn't spinning your compressor this is the first. aircon compressor clutch does not engage even with a + 12v supply to it A few basic reasons why an air conditioning clutch does not engage, even if you have a power supply down to the compressor. I found out how to test the A/C Clutch Cycling Pressure Switch , long story short its not working. Next moved on to the pressure and cycling switches (located on accumulator and compressor discharge tube) Again, they tested good, but I had spares, so replaced them anyway. A/C Clutch Cycle Switch - ([A/C Clutch Cycle Switch] TO ACCUM, BLACK; Quantity needed per vehicle: 1). Even though I live in Florida, on the rare occasion that I turn the AC off, I would like the thing to actually turn OFF. You disconnect the wire connector at the compressor and put a lead to the battery to see if the clutch engages. Here at Advance Auto Parts, we work with only top reliable A/C Clutch Cycle Switch product and part brands so you can shop with complete confidence. The cycle switch is almost always on or near the accumulator (large can). with a fixed displacement compressor and pressure cycling switch to control evaporator temperature. You can try a jumper wire at the compressor clutch relay socket (jumper the contact terminals only, NOT the coil terminals) or you can jump power directly to the clutch coil to verify compressor. Car AC Clutch Wont Engage When the car AC clutch won't engage you turn on the air conditioning and patiently wait for cool air that never comes. A replacement clutch, coil, and pulley (always replace them together) fixed the problem. a/c low pressure cycling switch is located on top of the accumulator. problem could be in the eatc module that send power to purple wire that feeds the ac pressure cutoff switch and ac clutch cycling pressure switch then feeds the ac compressor clutch solenoid. By continuing to use this site you consent to the use of cookies on your device as described in our cookie policy unless you have disabled them. Inspect and test before replacing! AC Accumulator / Drier. Remove the jumper from the plug. Again you have the option to set the cabin temperature. That aside, my next check was on the compressor. It has two small wires. so you didnt need to test the pressure switch, you need to test the compressor clutch. If you turn on the air conditioning and stand in front of the car and listen to the engine you will hear the AC compressor clicking every few seconds as it engages and disengages. Examining Air Conditioning Clutch Failures in the Field This guide can be used as a reference to diagnose clutch failures, and is specifically designed to help you differentiate between unwarrantable clutch failures and those that would normally fall under possible warranty consideration. Inspect the motor coupler. It is mounted in the low pressure side of the AC system and its purpose is to detect the flow of. Also, ignoring a simple voltage check on the pressure switch can lead to repeated compressor clutch failure. If the pressure is rising the switch will close at 31. If you don't add more r-134 to the system and allow the AC compressor to cycle you will destroy the compressor. The switch should open (stop compressor) at about 23# and close (start compressor) at about 43#. Receiving power at the wires, jumped both wires together and clutch engaged. Orifice tubes can become clogged and severely hamper A/C performance. This switch works to keep the air conditioner full of the refrigerant it needs, in order to keep the AC blowing cold air. It has finally gotten hot and it seems we are fully into air conditioning season (let’s hope it stays fo a while). While performing the checks, do not leave the relay bypassed. The cycle switch is almost always on or near the accumulator (large can). My AC would randomly start and stop intermittently, so I ensured that the system was charged and once I was assured that it was full I checked this switch and it was the culprit. A replacement clutch, coil, and pulley (always replace them together) fixed the problem. The cycling switch will typically be mounted to the accumulator. Low and behold. A worn-out pressure-cycling switch can cause air *conditioning compressor clutch failure, service experts warned. The cycling switch screws to the top of the accumulator / drier. I found out how to test the A/C Clutch Cycling Pressure Switch , long story short its not working. 5 psi, disengaging the A/C clutch. A series of relays and a resistor are used to control blower speed. Remove the jumper from the plug. Clutch plate air gap between the plate and the pulley in specs. Where is the pressure cutout switch on a f150 ac system & how do you jump it to start the compresser to draw in the - Answered by a verified Ford Mechanic We use cookies to give you the best possible experience on our website. on my vehicles, including my E-420, a full can of R134 will give enough pressure on the low side to start cycling the compressor even when vitually empty of R134. when i jump the terminals on the relay it comes on and cools like a champ. Your truck has a clutch cycling switch which is mounted in the side of the receiver/dryer. More importantly there are some vehicles that have specific problems with this electronically controlled torque converter clutch system. One of the most common problems is a low refrigerant charge, the low pressure switch prevents the AC clutch from engaging when the system is low on refrigerant. A simple test is to use a short wire, temporarily connecting the terminals. The clutch is pretty easy to test. 7) Test the pressure switch for continuity with an ohm meter. Please note that this switch has a square connector, for 1998-1997 there is another switch that has a oval connector. com ® permission to use it in future advertisements and promotions. Remove the component from the socket and test for a power signal and a good ground at the proper terminals. In this tech article VETTE provides an air conditioning troubleshooting guide to show you how to diagnose and repair common Corvette A/C problems - Vette Magazine the low-pressure switch will. This will help you keep the threading intact on the unit, as well as make sure that you do not drop any debris into the accumulator. My AC has gone out. If no click, check for power at the green wire at the compressor. The cycle switch will cut the power to the air conditioner clutch. you might have a bad pressure switch. 5 IN OUR PRODUCT You are purchasing a New A/C Clutch Cycle Switch-Pressure switch Universal Air Conditioner. Check the relays. Many technicians are aware that the pressure-cycling switch opens every time. Important: DO NOT USE A/C low pressure cycling switch, P/N 15035084 on the vehicles listed above. 3 cans is 2. I have a 2000 silverado lt z71 4x4 the compressor clutch will not engage. Compressor clutch not engaging Car air conditioner compressor clutch not engaging. What makes the clutch not engage?. connector terminals (1). If you are seeking top-quality and affordable air conditioning parts for your vehicle, then UAC products offered at CARiD are what the doctor ordered. The cycle switch is almost always on or near the accumulator (large can). When the pressure goes below 25 psi, the pressure switch cuts the power going to the compressor, making it shut off momentarily. New A/C Compressor / Clutch Assembly. Since your post does not state the MY, I am going to surmise that one wire is the clutch power and the other is the field coil ground. I changed the selector switch on the dash to all positions one at a time and observed the AC compressor. Testing compressor clutch/wiring: Key on engine off, Jump the A/C clutch relay from pin 30 to pin 87, Compressor clutch should "click". The thermistor should be suspected if you have excessive cycling, but normal pressures as did the OP. My AC has gone out. For instructions and other information, see the refrigerant compressor section elsewhere in this group. You’ll find that there’s an air gap between the compressor clutch and the bearing face. When the pressure has dropped to a certain level, this switch activates and allows high pressure from the other side of the A/C to enter in order to even out the pressure. The cycling switch cycles the compressor on and off on the low side of the system. I have electrical problem: the clutch won't engage on my Jeep Cherokee Laredo 92. it will cycle on and off very quickly at the start as the pressure drops, then builds. This is controlled by the low-pressure switch, which is installed on the accumulator. The switch is generally located on the side of the accumulator. Learn More. This switch works to keep the air conditioner full of the refrigerant it needs, in order to keep the AC blowing cold air. When the A/C cycling switch opens, the PCM will turn off the A/C clutch. com ® permission to use it in future advertisements and promotions. When activated, A/C switch allows compressor clutch to engage, operating compressor. That fuse doesn't feed the A/C clutch directly, so overdrawing current from a bad A/C compressor or clutch won't cause it to blow. Could be, but pressure is the 1st thing i would check. If low on refrigerant the cycling clutch switch will be open at the H / expansion valve at the firewall. The AC compressor on my 3. I've been looking and can't seem to find just the switch. From the fuse, that circuit goes to the A/C selector switch, then to the cycling switch, then to the high-pressure cut-out switch, then to both the PCM and the A/C relay in the CCRM. A/C Clutch Cycle Switch (SW9701C) by UAC®. Still no air. You can remove the connector for the pressure switch and check to see if you have power at either wire. 5V , RPM A/T more than 800RPMs -M/T more than 700RPMs. The air conditioning system is regulated by a few components. (70 degrees oustide about 70 psi on high and low sides - temp. Wear safety glasses. The cycling switch screws to the top of the accumulator / drier. TEST the system for normal operation. This is controlled by the low-pressure switch, which is installed on the accumulator. A full cycle of AC uses the entire wave of the south and north magnets. The PCM supplies a ground to do this. I do not know how either of them look and where exactly to find them. When it comes to your Hummer H2, you want parts and products from only trusted brands. I have a 2009 Honda Civic. when i jump the terminals on the relay it comes on and cools like a champ. With AC problems, yes you have AC problems, first thing I do is connect my gauges and power supply directly to the clutch coil. This switch is designed to make sure that the pressure stays at a consistent level so that the AC can function correctly. With engine running at cruising speed 44lb back pressure 225 high side. I know its probably the compressor but the only thing I'm not able to check is the A/C Clutch Diode. If you do so with the engine not running, you can then turn the compressor pulley by hand to make sure your compressor isn't locked up. Both times were at initial startup in the morning. Check clutch bearing. GM OEM Air Conditioning Low Pressure Clutch Cycling Switch. For instance, a leak in the system allows the refrigerant to escape. Electric Air Conditioning Fan. Fan Clutch Solenoid Resistance Test Hookup. With the sytem on, set at max cool, take the connecor off the pressure switch and one terminal of the wire should have battery volts. Before we begin with the actual troubleshooting, to properly troubleshoot the A/C system, it's extremely helpful to understand how the automobile A/C cycle works. the whole time i was filling it up the compressor kept cycling on and off, on for about half a second and off for 5 or 6 se. The switch senses system pressure and rapidly cycles the compressor on and off when the refrigerant is low. Had AC friend to check pressures and amount of coolant and all normal. Turns out that the AC clutch had worn down, and I needed to remove some of the shim between the front plate and the compressor shaft. The FOUR SEASONS Ac Clutch Cycle Switch contains no remanufactured components, and is designed to operate in either city or highway driving. The thermistor should be suspected if you have excessive cycling, but normal pressures as did the OP. Next moved on to the pressure and cycling switches (located on accumulator and compressor discharge tube) Again, they tested good, but I had spares, so replaced them anyway. I want to start from the most basic solution to the most expensive-complicated. A/C Compressor Clutch Cycle Switch by UAC®. However if the chill test works and you have an icing problem the icing is related to the position or contact of the end of aluminum capillary in the evaporator's coils. The place to start is gauge readings of the high and low side pressures. You should be able to pull the plug off and see if it makes any difference to your AC cutting in and out, and of course if we can find out the temperature it operates at I can finish my project, and you can test yours with a MM and immersing in oil. Clutch Cycling Switch. 1) check fuse #12 in under-hood fuse box , check fuse#30 in under-dash fuse box (both 7. I did that to mine while I was replacing all the o-rings in the system. so I looked for fuses and what not but that wasnt the problem. To create DC, you must take the AC and convert it to DC. With fans working as you describe, this is Hondas' order for troubleshooting. A/C Clutch Cycle Switch - ([A/C Clutch Cycle Switch] TO ACCUM, BLACK; Quantity needed per vehicle: 1). At Repco, we have all the Other Air Conditioning Parts items you need, including OES Air Conditioning Pressure Switch RH170. It lists for 38. This is a MOPAR replacement AC Low Pressure Switch for the above listed Jeep applications. Cycling is the compressor clutch engaging and disengaging in a uniform manner. Check blower switch for voltage at each position. occasionally this is enough to make the high pressure transducer see correct pressures and start to. Inspect and test before replacing! AC Accumulator / Drier. One of the things missing in the Pantera air conditioning system is a high/low pressure switch. Free shipping. You can remove the connector for the pressure switch and check to see if you have power at either wire. Located in Tulsa, Oklahoma, Honda Of Tulsa has the products for you. this is a signal that goes from the hvac control module to the switch then to the PCM input. Wear safety glasses. Failed power supply to the AC clutch caused by a blown fuse, bad pressure control switch, dash control module or a broken circuit wire. It just needs to be snug. When it comes to your Ford Expedition, you want parts and products from only trusted brands. the heater-A/C mode control switch; the low pressure cycling clutch switch; high pressure cut-off switch; compressor clutch relay; Powertrain Control Module (PCM). Relays can also switch multiple things on simultaneously while using one output, allowing, for instance, you to turn on your car's radio at the same time the antenna extends. A/C DOES NOT WORK With engine running and function control switch at NORM position, check for voltage at pressure cycling switch. Also check the compressor mountings for tightness. check for a short or open in red yellow wires at the ac pressure cutoff switch. The AC clutch is the same basic design as an electric PTO clutch. when i jump the terminals on the relay it comes on and cools like a champ. 2 - 16 guage leads Fits Ford Cycling Switch # E35Y-19E561-A. The other switch is the A/C Cycle switch and that is located on the tube coming from the middle of the engine bay behind the firewall. The thing is, a noisy air conditioner is also a sign of trouble, specifically with your compressor. If so, try the troubleshooting techniques described here. The cycling switch cycles the compressor on and off on the low side of the system. 5 air conditioner check. One of the parts of the air conditioner that is most likely to fail is the cycling switch. 1) check fuse #12 in under-hood fuse box , check fuse#30 in under-dash fuse box (both 7. Click on the button below to get an upfront quote for your car. Examining Air Conditioning Clutch Failures in the Field This guide can be used as a reference to diagnose clutch failures, and is specifically designed to help you differentiate between unwarrantable clutch failures and those that would normally fall under possible warranty consideration. This switch is made by GM to be an OEM stock fit in your C4 Corvette. Ground compressor clutch circuit. At Repco, we have all the Other Air Conditioning Parts items you need, including OES Air Conditioning Pressure Switch RH170. If you don't add more r-134 to the system and allow the AC compressor to cycle you will destroy the compressor. By uploading an image, you agree to give LMR. This shows that the switch is faulty. The cycling switch will typically be mounted to the accumulator. In this tech article VETTE provides an air conditioning troubleshooting guide to show you how to diagnose and repair common Corvette A/C problems - Vette Magazine Clutch-cycling switches. Air Conditioning System: Electrical For this issue of Fiero Focus, we're going to continue our electrical circuit path discussion topic; this time of the Air Conditioning (A/C) system. Check blower switch for voltage at each position. You can do it the way mentioned above, or you can test it another way. A biased switch contains a mechanism that springs it into another position when released by an operator. A cycling clutch switch is used to engage and disengage the compressor clutch according to the system’s low side pressure. Make sure you have the fan turned on medium. There are two basic types of automotive air conditioning systems. The switch senses system pressure and rapidly cycles the compressor on and off when the refrigerant is low. The switch will open and cause the system to stop operating under certain conditions which may hurt the system. I listed them in the order I would suspect them. UAC's line of electrical components includes the Switches and Relays that are necessary for the proper function of an A/C System. Jumping the pressure cycling switch is common practice on domestic CCOT systems, but the Civic is temperature cycled and fully controlled by the ECM. This switch is on the accumulator and cycles the compressor clutch. The AC compressor does not cycle like would expect it to. Clothes are too wet after spin cycle. Air Conditioning Clutch Cycling Switch Stay with the parts brand your vehicle came with and get the GM quality you know and trust with ACDelco GM Original Equipment Air Conditioning Parts. Best diagnostic tool is a set of R134a gauges. In this tech article VETTE provides an air conditioning troubleshooting guide to show you how to diagnose and repair common Corvette A/C problems - Vette Magazine Clutch-cycling switches. A/C-HEATER SYSTEM 1995 Chevrolet Tahoe 1995 AIR CONDITIONING & HEAT General Motors Corp. I have 12V going through both pressure switches. this high press cutout switch does not have 12volts to it. Yes INSTALL a new A/C cycling switch. clutch relay. If the compressor still does not operate properly, refer to HVAC Compressor Clutch Does Not Engage diagnostic in SI. Check if this part fits your vehicle A/C Clutch Cycle Switch. I took it to a mechanic who applied power directly to the compressor, forcing it to come on. If the clutch engages, then check the power supply to the clutch, including the system protection devices and electronic compressor controls. This switch works to keep the air conditioner full of the refrigerant it needs, in order to keep the AC blowing cold air. i then checked the pressure with the car off and it was at about 100 psi. I've determined that whatever provides the grounding path for the clutch relay does not do it. One of the most common problems is a low refrigerant charge, the low pressure switch prevents the AC clutch from engaging when the system is low on refrigerant. To look at the condition of the compressor, you need an ac manifold gauge set so you can see the refrigerant levels in both sides of the ac system, and how well the compressor is working (if at all). The switch will open and cause the system to stop operating under certain conditions which may hurt the system. Repairing The A/C Control Switch. Check if this part fits your vehicle A/C Clutch Cycle Switch. I took it to Goodyear and they tested it. Your car's air compressor pressure switch, is responsible for giving and cutting off power to the air compressor of the air conditioning system. With the AC compressor running it should read ~40psi. If you’re here, chances are you’ve tried to recharge your AC system and found a compressor clutch not engaging issue. Electric Air Conditioning Fan. By continuing to use this site you consent to the use of cookies on your device as described in our cookie policy unless you have disabled them. The most common type is a "push-to-make" (or normally-open or NO) switch, which makes contact when the button is pressed. This is a MOPAR replacement AC Low Pressure Switch for the above listed Jeep applications. Technician B says the air conditioning system is overcharged. In isolated situations where the AC compressor clutch relay has a unique part number we test it the old-fashioned way. Free shipping.