How to Restore the Mercedes-Benz Blind Spot Assist System When It Stops Working?
4 Answers
You need to go to a 4S shop for computer detection, and generally, an upgrade can solve the problem. Here is the relevant introduction: 1. Rear radar sensor: The left rear and right rear bumper radar sensors are located on the rear bumper, and their function is to monitor objects (obstacles or vehicles) in areas that cannot be observed by the outside rearview mirrors. The monitoring distance is S=0.18∼30m, the resolution is S=0.04m, the detection angle is 80°, and the tracking detection angle is 130°. 2. Front radar sensor: The left front, right front radar sensors and the front long-range radar sensor are located on the front bumper, and their function is to monitor the environment in the front area of the vehicle. The maximum detection distance is 30m, and the maximum angle is 130°. 3. Blind Spot Assist System warning light: The left and right Blind Spot Assist System warning lights (M21/1e2 and M21/2e2) are located on the left and right outside rearview mirrors, respectively, and are actuated by the left front and right front door control units. After actuation, they appear red, aiming to warn the driver.
Over the years of driving a Mercedes, I've encountered the blind spot assist stopping a few times, often due to minor issues. First, check the sensor position on the rear bumper for any mud, snow, or debris blocking it, and clean it with a damp cloth, then drive around to let it detect. If that doesn't work, restart the system by turning off the engine, locking the car, waiting for 5 minutes, and then starting it again. Alternatively, go into the car's settings menu and toggle the driver assistance options. If it still doesn't function, the software might need an update—connect to the car's network to download and install the upgrade. Hardware-wise, sensor damage or wiring issues are not uncommon, so it's recommended to visit a 4S shop to check the fault codes with a diagnostic tool. When washing the car, pay extra attention to cleaning the sensors, especially after rainy days when humidity can have a significant impact. When it fails, changing lanes on the highway can be dangerous, so safety first—don't ignore it.
As a car enthusiast, I've analyzed the Mercedes blind spot assist shutdown. The sensors are located on both sides of the rear; cleaning dust and water stains is the first step. Then check if the system settings are turned off or accidentally triggered a restart function. Software updates might fix bugs - download firmware via the central control screen internet connection. Look for relevant fuses in the fuse box but don't replace them manually unless you're knowledgeable. Using an OBD tool to read error codes is the most accurate way to locate faults, otherwise just drive to a professional repair shop. This system detects vehicles in the side/rear via radar and alerts through steering wheel vibration - quite practical. Regular cleaning during maintenance prevents signal interference. Handling simple issues yourself saves both money and time.
Blind spot assist failure is too dangerous. My suggestion is to first park and clean the sensor area; restart the vehicle to see if the system recovers automatically; check the menu settings to confirm it's turned on; persistent issues indicate hardware failure, such as sensor damage or cable problems, and you must contact a Mercedes-Benz dealer for diagnosis and repair without delay; driving without this system increases risks, especially on highways or at night, so stay vigilant and use mirrors for manual observation—safety comes first.
