The air conditioner in your Mercedes absorbs the heat and humidity from the cabin, and in return, it circulates cool, dry air for your comfort. The system could fail due to old age or poor maintenance, thereby affecting its cooling capacity.
Driving with a failed air conditioner is usually uncomfortable, especially during the brutal summer heat. Discussed below are the causes, possible symptoms, and solutions of a failing air conditioning unit.
Causes of a Faulty Air Conditioner
- Faulty compressor: The compressor remains an important component of the AC system in your Mercedes. It pressurizes the refrigerant and enables the continual flow of it through the system. Your Mercedes compressor performs these functions by cycling on and off repeatedly. So, when it fails, the air conditioning system suffers.
- Leaking refrigerant: The refrigerant operates as a lubricant to the air conditioning system. When you notice a decrease in cool air circulation, it may be due to leaking refrigerant. This leak could have resulted from a worn-out valve, weak seals or other damaged parts. If left unattended, a leaking refrigerant would ultimately cause your air conditioning system to break down.
- Broken or blocked condenser: The condenser performs an important role in the functioning of your air conditioner. It cools the vapors from the refrigerant and achieves this by converting hot air into cooler refrigerant liquid. However, the condenser breaks down or becomes clogged over time due to dust or debris built up. The air flow becomes restricted when this happens, hindering the system’s capacity to blow cool air.
- Electrical Issues: The air conditioning unit in your Mercedes is powered by your vehicle’s electrical system. The system’s compressor, clutch, control module and pressure switches are connected to the electrical system. If the system fails, they all fail. The failure of these components would consequently cause the air conditioning unit to break down. However, electrical system failure is not as common as other causes discussed above.
Symptoms of a Bad Air Conditioning System
Several symptoms alert you to an issue with your Mercedes air conditioning system, and they include:
- Hot air from vents: This is the most obvious sign that something is wrong with the system. The main function of your vehicle’s air conditioning system is to cool the air entering the passenger cabin. However, when the system starts to fail, it begins to blow hot air, which is mostly a sign of a failed compressor.
- Unusual Noise: Apart from the usual sound the system makes while running, you may notice unusual weird noises when it starts failing. It could be a grinding or whining noise and usually originate from a failing compressor.
- Fluid leaks: The air-conditioning system has internal components, including bearings which help prevent the refrigerant from leaking out of the compressor. When the refrigerants leak out due to failed bearings, it affects the system’s cooling capacity.
- Cooling Fan Control Unit Malfunctions: The cooling fan control unit could also cause your Mercedes air conditioning system to fail. The cooling fan control unit is a control module that connects the air conditioning fan to the rest of the AC system. A broken connection can cause air conditioning system problems.
- Unpleasant smell from AC vent: If your air conditioner is functioning properly but circulates an unpleasant smell with the cool air in the cabin, there is an issue with your air filter. Your Mercedes has an air filter that filtrates all the unpleasant odor from the cabin. When it becomes clogged, the result is the foul smell being circulated by the air conditioner.
Whenever you notice any of the symptoms discussed above, you should contact a Mercedes technician to rectify the issue.
Hayes European for your Air Conditioner Maintenance and Repairs
Whether scheduled maintenance or full-blown repairs of your air conditioner, at Hayes European, our goal is to provide every customer with quality service. We pride ourselves on delivering quality service to European, Japanese and American vehicles using the latest factory grade tools and equipment.
We are located in Capitola, CA, and have provided impeccable service to Santa Cruz, Aptos, and Soquel drivers. We also offer scheduled maintenance, inspection, oil change, brakes, electrical diagnosis, engine repair, transmission repair, fluid leaks, and more. Please call or visit our shop to schedule your next service appointment.