What are the reasons for the sudden loss of air flow in a Mercedes-Benz air conditioner?
2 Answers
There are three main reasons for the sudden loss of air flow in the air conditioner. Blower motor failure: The blower motor is the core component responsible for air flow in the car's air conditioning system. If it is damaged, the air conditioner will definitely not blow air. Causes of blower motor failure may include overheating and damage to internal coils or capacitor failure. You can check for faults by turning the air conditioner's fan speed and air volume to the maximum and listening for the sound of the blower motor. If there is a fault, it needs to be repaired at a 4S shop or repair shop. Filter clogging: Filter clogging is one of the causes of air duct blockage and the most common one. Outside air passes through the air conditioning filter to be cleaned before entering the car, which can trap a lot of airborne debris, making it prone to clogging. You can remove the air conditioning filter to check if it is clean. Control system failure: If it is not one of the above two reasons, then there is a problem with the car's air conditioning control system. The air door, control switch, or the car's air conditioning computer could be the cause of the failure. It is best to go to a 4S shop for inspection and repair.
Last time my friend's Mercedes-Benz C-Class also encountered the issue of no air coming from the AC. Upon inspection, it turned out the blower motor had failed. The blower motor is like the heart of the AC system, responsible for pushing out the cooled or heated air. These vehicles typically use an electric blower, which can stop working when it reaches the end of its lifespan or if the carbon brushes wear out. Another possibility is a malfunction in the control module, which regulates the fan speed—if it fails, there will be no response. It's also worth checking if the corresponding fuse in the fuse box has blown. For Mercedes-Benz AC systems, the fuse is located in the black box on the left side of the engine compartment. The most troublesome issue is when the evaporator coil freezes and blocks the air ducts, which is particularly common when running the AC at the lowest temperature during long drives. If you encounter no airflow, don't panic immediately—try increasing the AC temperature by a few degrees and wait for about ten minutes. If the airflow returns, it's likely a freezing problem.
