How to Do a Mercedes Air Conditioning Reset

One of the most common complaints of Mercedes users is issues with the air conditioning system. In many models, the AC keeps blowing hot air even after recharging the coolant. It is a frustrating problem, especially during the summer when it is almost impossible to drive a car without the AC on. A Mercedes air conditioning reset is a possible solution. Do you know how to do it? Is there any other way to fix the glitch?

4 Common Mercedes Air Conditioning Problems

A faulty Mercedes air conditioner is one of the common problems in the summer due to many reasons such as slow cooling time, not deep cold, the car only has hot wind without cold wind or smells musty…These are the 5 common issues when repairing a Mercedes air conditioner that drivers often experience:

1. Dirty air conditioner filter

If you are turning on the Mercedes AC to the highest setting and it still does not feel cool, it is most likely caused by a dirty air filter.

Over time, if it is not cleaned regularly, the dirt will stick to the filter mesh, and it will form a thick layer, causing the wind to be trapped in the indoor unit without entering the car’s cabin. In this case, the only solution is to clean the filter. According to the manufacturer’s recommendations, the air conditioner filter should be checked, cleaned, and replaced periodically to ensure the cooling capacity of the system.

2. Faulty AC fan

A fan malfunction is one of the mechanical issues that can cause your Mercedes AC issues. If the AC blower turns on but it is not cool, it may be due to the following reasons: a broken circuit, faulty capacitor, broken coil, or the fan motor is short-circuited…

In hot weather, the air conditioning system in cars is used frequently, so there are often unusual incidents that make drivers feel uncomfortable in the hot, stuffy atmosphere. To save time, give your car to trusted mechanics. 

3. Leakage AC refrigerant

If the car engine needs the oil to operate smoothly, the refrigerant also has the same function in the air conditioning system. On average, your car will lose about 15% of the refrigerant a year. If the amount is over the standard, it will cause some problems for the AC system. The culprits behind the AC refrigerant leak can be a damaged seal, valve, or other parts in the AC. If you realize the AC Mercedes is not releasing cool air. The reason can be a low refrigerant.

4. Ineffective heat radiator outdoor unit

It’s also one of the common problems happening to AC Mercedes or even other car brands. Because the outdoor unit is usually located near the cooling tank. When the transmission or the engine is overheated, it will affect the heat process of the outdoor unit. In the event that the outdoor unit doesn’t cool down, it will cause the high-pressure gas pressure to rise above the specified level, and the air conditioning system will automatically disconnect the cold block to preserve the system. Besides, the outdoor unit’s heat dissipation is not good, it may also be because the outdoor unit fan is dirty or malfunctioning. Therefore, it is also necessary to check the outdoor unit fan.

In addition to 4 main problems above, other issues of Mercedes AC could be a concern for some drivers: 

  • A faulty compressor
  • The electrical system malfunction
  • Condenser leakage

Take your car to a trusted mechanic to have the right diagnosis. 

How To Do A Mercedes Air Conditioning Reset?

All Mercedes cars have a series of service lights that there is something wrong with an internal component or system. However, there might not be any damage in the AC unit when it is blowing warm air or not running properly. It could be a temporary fault and a reset is likely to be enough to restore the normal function.

Sometimes, the process is called a Mercedes climate control reset. The reset procedure is similar no matter whatever you call it. However, if the AC shows any trouble after resetting, you have to take it to a servicing shop or the dealership for a permanent fix.

mercedes climate control reset
Resetting the AC is a simple task. (Photo: mercedesclub)

Mercedes air conditioning reset

Step 1: To do the resetting, you have to insert the ignition key into its slot and turn the ignition cylinder to position ‘2’. This is the highest point that the cylinder can go without activating the engine.

Step 2: Press the buttons for recirculating air and defrosting at the same time and hold them for somewhere between 5 to 10 seconds. To be on the safe side, hold them until their LED lights start flashing.

Step 3: Wait for about a minute for the LED lights to stop flashing. When they do, turn the car off. Wait one more minute before restarting the engine.

The AC system is reset now and the hot air blowing problem is likely to be solved.

If your Mercedes car does not respond to this procedure, you should check the owner’s manual. For example, if you want to know about Mercedes E320 AC reset, it is better to check the manual and follow the manufacturer’s recommendations.

Visualizing detailed steps in this video:

AC Blowing Hot Air: Other Possible Reasons

If a Mercedes air condition reset does not work, the following reasons could be causing the trouble:

When the AC is releasing hot air, the possible reason could be a defect in the damper. The component is in charge of the air path that goes into the cabin. Check the onboard computer if it can verify the damper’s position. If one of the controls is ‘out of range’, the damper is surely the root of the problem.

mercedes air conditioning reset
Look for other reasons when resetting does not work. (Photo: specialist-auto)

Read more :

A leak in the AC refrigerant is most likely the culprit when the blown air is not hot but not cold either. It could also be a clogged AC fan blower motor. The first one could result in an expensive repair but fixing the second component is easier and less inexpensive.