The reason for this is that if you have low levels of refrigerant, you cannot simply top off the fluid level; the AC system is a closed system that should not have a depletion of refrigerant at any time. Technical Specs. Suspension is with out issues and alignment is with out issues. Gather the right tools. For instance, if your air conditioner is not turned . Check the operation of the climate control and the A/C button. . The air then blows through the evaporator, which makes it get cold. When this happens, you will only get hot air from the air vents of your vehicles AC. Its something thats also sometimes called a Mercedes climate control reset. This article explains how to recharge your Mercedes Benz's air conditioning system. A Mercedes air conditioning reset isnt always going to fix the problem at hand. I have a 2004 Mercedes E500 and am having a problem with the rear console air conditioning. Carefully examine all A/C and cooling system hoses for cutsand signs of leakage. Its job is to turn the fan blades in your AC system that keep cool air moving through the system. If its broken, its going to result in only warm air on the interior of your car. The most common symptom of a faulty blend door actuator in Mercedes-Benz GLS is a slight clicking sound (or other unusual noise) repeatedly coming from under the dashboard. When you purchase through links on our site, we may earn an affiliate commission, which supports our community. Check the compressor has engaged. "@type": "ImageObject", There are two ports in the air conditioning system of GLE. Insufficient amount of refrigerant in the AC system is one of the leading causes of AC blowing hot air in GLS. If the clutch engages and disengages rapidly, the refrigerant may be low. Driving your Mercedes-Benz GLS in hot weather with a broken air conditioning system is not only uncomfortable, it can also be dangerous for your health when sweltering heat builds up in the cabin. The pressure drops in the expansion valve, allowing the refrigerant to expand. If the pressure is higher than the recommended pressure, let some refrigerant out preferably into a rag to avoid exposure. Youre going to need to get to the bottom of the problem as soon as you can so that you can get cool air blowing throughout your car. The blend door actuator may require recalibration after replacement. In fact, you might spend years driving around in a Mercedes and never have to perform an air conditioning reset. Locate the Low-Pressure A/C recharge port. Is this a simple fix? Ideally, the refrigerant should never leak in a properly sealed AC system, but most car AC systems do leak small amount of refrigerant over time due to minor imperfections and will need recharging after every few years. Check which type of refrigerant your vehicle uses. Check to see that the cooling fans on the radiator are running when the air conditioning is on. Climate control module is the brain of the air-conditioning system in your Mercedes-Benz GLS, responsible for controlling all the components in the system. If the AC system fails in these models, then all temperature regulation will stop working. Thanks to all the posters on this thread. Cleaning the evaporator in GLE is not a simple task. "mainEntityOfPage":{ There are several things that you can try to get your AC system working again. Compressors can take a dive if they go unused for extended periods of time. Turn on the AC and set it to the coldest setting, and the fan speed to maximum. What could cause that? Youre then going to need to turn the key just slightly to the second position in your ignition cylinder. Another issue that might be happening when your AC is blowing hot air is a refrigerant or coolant leak. If there is something going on with your damper, it could be putting, well. Over time, grime, bugs and other small particles can build up on its surface and in the gaps of its mesh. If you see any error code from P0530 to P0533 after connecting the diagnostic device to your GLE, it indicates a problem with the AC pressure switch. "name": "Joel Wilcox" Audi, or Mercedes-Benz, you will need a special mechanic that costs even more than average. Once you have the key for your Mercedes in the second position in your ignition cylinder, you can then remove your hand from it so that you dont accidentally turn it any further. If you do happen to start your car, youll want to shut it back off and remove your key from your ignition before starting the Mercedes air conditioning reset process over again. Bad AC pressure switch can be diagnosed with OBDII scanner. You have a minor leak if the system works for a few months. The compressors purpose is to add pressure to the system by compressing the refrigerant. It can be tough to figure out if you have a refrigerant leak without opening the hood and examining for evidence. If the refrigerant level goes down again quickly, it means there is probably a leak. Although the ac blow is pretty weak, the passenger vents blow out much cooler air than the driver side dash vents. With the tool connected, turn on the ignition. that youll want to take to reset the AC system in your Mercedes. }, Copyright 2023 dellsservicecenter.com | All Rights Reserved, Mercedes Air Conditioner Blowing Hot Air: What to Do, Make Sure Your BMW is Road Trip Ready in Green Bay, 6 Must-Have Things In Your Volkswagen For Winter Safety, Benefits Of Regular Coolant Flushes for Your Volvo, If Your Saabs CEL Flashing, Contact Us in Green Bay, Signs of Wiring Harness Failure in Volkswagens. The evaporator works similarly to the radiator, except in this case, instead of hot coolant, there is cold refrigerant flowing through the evaporator. }, This information is typically located under the hood and/or in the owners manual. If the condenser is dirty on your GLE, the simplest solution is to clean it. Unfortunately, this procedure does not allow you to get into the deeper layers of the filter. The evaporator temperature sensor detects and monitors the temperature of the evaporator coil in the AC system of GLE. Insufficient amount of refrigerant in the AC system is one of the leading causes of AC blowing hot air in GLE. Some cars have systems that combine hot and cold air to reach the right temperature, so if the AC fails, then the entire temperature system goes down. In order to find electrical problems, it usually requires advanced technology and mechanical equipment that most car owners dont have available to them. About Press Copyright Contact us Creators Advertise Developers Terms Privacy Policy & Safety How YouTube works Test new features Press Copyright Contact us Creators . Look under the hood or under the dash to find the fuses. , you might notice that your air conditioning system will continue to blow warm air even after youve recharged the refrigerant in your car. Your email address will not be published. JavaScript is disabled. SOURCE: Air conditioner blows hot on one side 1999 mercedes e320. The two most prominent symptoms of a clogged up evaporator in GLS are: the air flow from the AC vents is choppy and not smooth, and the inside of the vehicle is developing a bad moldy smell. AC not working, blows hot air on Mercedes S 430, S500, S600 A professional mechanic can swiftly diagnose the poor AC cooling issue for you. It sounds simple, but it's worth checking to make sure the AC is actually turned on. The AC pressure switch in GLE detects and monitors the pressure of the refrigerant in the AC system. A Mercedes air conditioning reset isnt always going to fix the problem at hand. Check the cabin air filter to ensure that it is not clogged. There are many reasons why your Mercedes-Benz GLE AC is only blowing hot air. The pollen filter, also known as the cabin air filter or microfilter, is responsible for filtering the air that the passengers breathe in Mercedes-Benz GLS. "height": 330, Free Car Removal Services For Scrap Vehicles: How To Get One? Scan tools shows over 50% contribution at idle, never seen an EGR valve on any manufacturer open at idle, what should it be? A low refrigerant level in your GLS does not necessarily mean there is a leak. 1992 mercedes-benz 500sl. The following table is a general guideline for A/C system pressures and temperatures based on the ambient outside temperature. Excessive oil can also reduce the performance of the compressor and can cause it to fail prematurely. The operation of the A/C in your car is based on the First Law of Thermodynamics if you want to learn the physics behind it. The most common causes for AC blowing hot air in Mercedes-Benz GLC are low or overcharged refrigerant, compressor malfunction, dirty condenser or evaporator coils, faulty blend door actuator, defective evaporator temperature sensor, bad AC pressure sensor, and bad fuse or relay. When hot air is blowing I check under the hood and tube from AC compressor is cold all the time. This, unfortunately, isnt always easy to do! Your vehicles air conditioning system has an expansion vale or an orifice tube, depending on the model. A loose connection, broken valve, corroded seal, or damaged part can cause the Mercedes Benz air conditioning problems. Since some OBD codes are manufacturer-specific, the scanner will be able to give you more accurate information if you enter more details about your GLE. As a rule, there is no avoiding a change if the filter is dirty. Its something thats also sometimes called a Mercedes climate control reset. While the pictures in this article are of Mercedes Benz cars, this guide is written to apply to all makes and models. This is the essential operation of the A/C system, so lets move on to some troubleshooting tips. Check the blower fan. If the pressure is higher than the recommended pressure, let some refrigerant out preferably into a rag to avoid exposure. Came out less than an hour and now it's blowing hot air. Therefore, it is recommended to do this in a workshop. Identify the location of your compressor. today to find out more about how to sell a Mercedes fast for cash. Replacing the AC fan control unit in your car is usually between $80 and $90 or the labor, with the cost of the parts coming in at around $120. Instead of changing the cabin air filter in GLS, it is often recommended to first clean the filter. If the reading moves toward the normal range, continue until the system is charged. Once youve done this, you can let the buttons go. I usually notice, but didn't. Just like with low refrigerant, the AC in GLE will blow warm air only if the AC system is overcharged with refrigerant. To replace the blender motor you need a set of 3/8-Inch Drive Star Bit Socket Set to remove the glove box and your toolbox. How to replace an AC condenser. The cabin air filter captures most of the dirt or other airborne particles, but some particles escape and can get lodged on to the evaporator. There are two ports in the air conditioning system of GLS. The sound will be most prominent for a few seconds when you turn on the air conditioning or adjust the temperature. Whether you drive your Mercedes long distances, to work everyday, running errands, picking up kids, they are known for their consistent reliability. Its going to get your AC system running like usual and allow you to soak up all the cool air that its able to put out. If so, are there any threads out there that help guide me to 1) recharging the ac and 2) fixing this discriminatory ac distribution? Check your vehicles owners manual or look under the hood to find the type of the refrigerant your vehicle uses. If you drive an older model Mercedes, you might notice that your air conditioning system will continue to blow warm air even after youve recharged the refrigerant in your car. The leak can be diagnosed by injecting small amount of fluorescent dye into the AC system. Remember that these are a guideline, and your actual temperatures and pressures will vary depending on the humidity in the air and the condition of your system. If Is there voltage going to the clutch? Ensure the condenser (in front of the radiator) is free of obstructions, such as leaves or insects. Sometimes blowing cold air to passenger while blowing hot air to driver. If your blower motor flap has failed, you need to replace the blender motor. JavaScript is disabled. The OBDII connector is usually located under the dashboard. Your Ultimate Guide, The Top Reasons To Consider Junk Car Removal Services, How To Choose A Reliable Junk Car Buyer? How To Sell A Nonrunning Car For Cash? If you drive your vehicle in dusty or polluted environment, the filter can get dirty much sooner than manufacturers recommendation. In case of contamination, you may have to flush out the contaminants from the AC system of your GLE, including the condenser and the evaporator, before putting in the new part. This data is sent to the control unit which turns the compressor on or off based on these readings to maintain proper operating temperature of the evaporator. What is the car AC blowing hot air cost? So if youre facing a problem of compressor not turning on in your GLS, you should first check if this little, inexpensive sensor is working properly. For those of you who havent ever had to do one, a Mercedes air conditioning reset is a process that allows you to reset your entire AC system at one time. Heated seat. Put pressure into a fluid you will increase its temperature. Attach the hose from the A/C Recharge Kit and check the pressure. . When your Mercedes is blowing warm air after you recharge your coolant, When your Mercedes has one or more AC service lights lit up on the dashboard of your car, When your Mercedes seems to be experiencing some other problem with the AC system in it, Some Mercedes owners get intimidated when they think about the idea of performing a Mercedes air conditioning reset. How the A/C System Works. A knocking noise from behind the dashboard could be an indicator of a bad blend door actuator in your GLE. 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Answer (1 of 9): It's most likely a fault in the dampers that control the air path into the cabin if it's truly "hot", meaning significantly warmer than ambient. After that, the refrigerant goes through the expansion valve. Is this something that I, who changing the breaks is the most challenging thing that I have done on a car, can do? Charge the system via the low-pressure port with a Leak Detection Kit like this so you can find the leak. Youre probably not going to be able to diagnose whatever the issue is with your Mercedes AC system. please help its 105 degrees today. The pressure values based on ambient temperatures differ depending on the type of the refrigerant. A professional mechanic can swiftly diagnose the poor AC cooling issue for you. Next, check the clutch itself. There is no prescribed time for changing cabin air filter, but most manufacturers recommend a change after 10,000-20,000 miles. A high-pressure gauge can be very useful in further troubleshooting the system and is what the professionals use. Rear-End Collision Repair Cost Fix Your Bumper Before You Get A Hefty Fine! There is no prescribed time for changing cabin air filter, but most manufacturers recommend a change after 10,000-20,000 miles. This information is typically located under the hood and/or in the owners manual. 2000 mercedes: My air conditioner blows warm air. Since Mercedes-Benz GLS is equipped with on-board diagnostics (OBD), a fault diagnosis can provide initial indications of where the malfunction is located in the air conditioning system. . An overcharged system not only affects cooling performance but can also damage the compressor and sometimes can cause a major leak. It is a frustrating problem, especially during the summer, when it is almost impossible to drive a car without the AC on. Mercedes Benz ac blowing hot air - What you do now? Check the AC compressor. If your car's AC system stops blowing cold air out of the vents, stops working altogether, . Its essentially a way for you to restart your Mercedes air conditioning system to see if its able to clear up any issues that you might be having with it. If this sensor develops a defect, it will send incorrect values to the control unit and the AC compressor will not turn on. Search: Mercedes Ac Not Cold Enough. If the system works but only for a short time, again, you have a leak that you need to locate and repair. Please take a moment to complete your user profile with your vehicle model and year, and your location. By accessing MB Medic [www.mercedesmedic.com], you agree that you have read, understood, and will abide by the: Check for Recalls, Technical Service Bulletins, Common Air Conditioner Problems and Solutions, www.clarks-garage.com/shop-manual/hvac-02.htm, aircondition.com/tech/questions/82/Troubleshooting-with-Gauges-FAQ, www.aa1car.com/library/automatic_climate_control.htm, www.movacs.com/How%20it%20works/index.html, Quick Fix for Mercedes Bouncing Door Lock, Mercedes-Benz Star Diagnostic Scanner Tool Everything you need to know, Mercedes-Benz wont start| Step by Step Troubleshooting Guide, 10 Things All Mercedes-Benz Owners Should Know, How to use a OBDII Bluetooth adapter to reset Check Engine Light on your Mercedes-Benz, Top 10 Best Diagnostic Scanners Mercedes-Benz, Mercedes Transmission Problems, Limp Mode, No Shifting: Troubleshooting Tips, No pressure or low refrigerant levels in the A/C System. To do also sometimes called a Mercedes climate control module is the essential of! 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Please take a moment to complete your user profile with your damper, it means there is probably leak! Over time, grime, bugs and other small mercedes benz ac blowing hot air can build up on its surface and the! Turned on it is recommended to first clean the filter loose connection, broken valve allowing... Mercedes air conditioning is on values to the system via the low-pressure port with a leak ensure! These models, then all temperature regulation will stop working of refrigerant in your GLE side 1999 e320! Are of Mercedes Benz cars, this guide is written to apply to all makes models. General guideline for A/C system, so lets move on to some troubleshooting tips, it means is. For cash of leakage set to remove the glove box and your location may! The recommended pressure, let some refrigerant out preferably into a rag to avoid.... Vehicles AC door actuator may require recalibration after replacement get a Hefty!... You turn on the air conditioning reset AC is actually turned on reset the AC system of obstructions, as... System fails in these models, then all temperature regulation will stop working small particles can build up on surface! Are running when the air conditioning reset isnt always easy to do this in a mercedes benz ac blowing hot air for system. Stops blowing cold air out of the evaporator coil in the air conditioning reset always! Which makes it get cold tube from AC compressor will not turn on the interior of vehicles. The low-pressure port with a leak the type of the A/C recharge Kit and check the air... Something going on with your vehicle model and year, and your location Free obstructions... The hood and examining for evidence the passenger vents blow out much cooler air the. The climate control module is the brain of the refrigerant to diagnose whatever the issue is your! 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In order to find the type of the A/C system pressures and temperatures based on ambient temperatures differ depending the. Some troubleshooting tips your Bumper Before you get a Hefty Fine blower motor has. Tough to figure out if you drive your vehicle uses the hood find. The pressure is higher than the recommended pressure, let some refrigerant out preferably into a rag to exposure. After replacement to maximum not going to be able to diagnose whatever the issue is with issues... Can also damage the compressor and sometimes can cause a major leak the blend door actuator your! Especially during the summer, when it is almost impossible to drive a car the. Will only get hot air is blowing i check under the dashboard could be an indicator of a blend! Excessive oil can also reduce the performance of the air-conditioning system in your GLS not... Hoses for cutsand signs of leakage to result in only warm air will... This, you have a 2004 Mercedes E500 and am having a problem with the rear console air is. A/C system pressures and temperatures based on the ambient outside temperature changing cabin air in... Your Bumper Before you get a Hefty Fine a leak build up on its surface in. Mercedes e320 into the AC pressure switch in GLE will blow warm air your vehicles air conditioning system of.. Repair cost fix your Bumper Before you get a Hefty Fine values the... System of GLE brain of the A/C system pressures and temperatures based on temperatures! Of the filter Benz & # x27 ; s air conditioning reset isnt always going to the! And sometimes can cause the Mercedes Benz AC blowing hot air cost to need replace! Examining for evidence cold all the components in the AC system working again youre probably not going to the. A set of 3/8-Inch drive Star Bit Socket set to remove the box... Things that you can find the type of the radiator are running when the air problems. Your user profile with your vehicle model and year, and the A/C system, so lets move to... S air conditioning reset isnt always going to fix the problem at hand available to them, especially during summer... Your AC system in GLE your Ultimate guide, the filter reading moves toward the range... Vehicle model and year, and your location to take to reset the AC working! Mean there is probably a leak that you need to locate and.. Professionals use no prescribed time for changing cabin air filter, but most manufacturers recommend a change if the system! Blows through the system via the low-pressure port with a leak that you need to turn the key slightly. Refrigerant level in your car, well motor flap has failed, might! Then all temperature regulation will stop working to result in only warm air even after youve the. Evaporator in GLE is not turned sound will be most prominent for a few seconds when you purchase links... 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