Where is the air quality sensor located in the Mercedes-Benz E300?

[ORuby]

The air quality sensor in the Mercedes-Benz E300 is located in the drainage channel, near the outer air conditioning filter. Function of the sensor: A sensor is a detection device that can sense the measured information and convert the sensed information into electrical signals or other required forms of information output according to certain rules, to meet the requirements of information transmission, processing, storage, display, recording, and control. Characteristics of sensors: The characteristics of sensors include: miniaturization, digitization, intelligence, multifunctionality, systematization, and networking. Existence and development of sensors: The existence and development of sensors give objects senses such as touch, taste, and smell, making objects gradually come to life. They are usually classified into ten major categories based on their basic sensing functions: thermal sensors, photosensitive sensors, gas sensors, force sensors, magnetic sensors, humidity sensors, sound sensors, radiation sensors, color sensors, and taste sensors.

[Enid]

I've noticed the air quality sensor location on the Mercedes-Benz E300 several times. It's located on the inner side of the front grille near the driver's side, or to be more precise, usually near the ventilation opening behind the bumper. This allows it to directly detect external air quality and helps automatically switch between internal and external air circulation when we use the AC. I remember last time during car wash, the technician pointed it out to me - a small plastic block-like component with ventilation holes. You can feel slight vibration when touching it gently, and it generates some heat when operating. When driving through tunnels or high-pollution areas, it immediately alerts the system to filter the air, which is particularly useful for family members with respiratory sensitivities. I recommend checking for dust accumulation around the sensor annually to prevent data misreading that might affect AC performance.

[LaMakayla]

A novice friend who drives a Mercedes-Benz E300 shared with me that the air quality sensor is often hidden under the windshield wipers or near the air conditioning intake inside the dashboard, specifically located in a small area below the front of the car, close to the inner side of the front bumper. The sensor is mainly responsible for real-time monitoring of external air conditions. Whenever pollution levels spike, a small light on the dashboard will illuminate or the air conditioning fan speed will adjust. I’ve clearly observed this in city traffic when the AC automatically switches to recirculation mode—super smart. As a new car owner, it’s important to get into the habit of checking the location of this component. Don’t underestimate it; if it malfunctions, the AC performance will suffer, compromising travel comfort.

[IsabelaLee]

I often tinker with car repairs myself. The air quality sensor for the Mercedes-Benz E300 is usually located at the air intake of the vehicle's front ventilation system, typically in a small housing behind the front grille or near the bumper mounting points. The position is relatively easy to find—just remove the protective cover to access the wiring connector. The sensor itself is a compact module with a filter mesh. When performing DIY maintenance, remember to disconnect the power cable first to prevent short circuits. Clean any dust blockages before replacement. I once experienced abnormal sensor operation causing unpleasant odors from the AC vents, but the issue disappeared after a simple cleaning.