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How the Active Hood Works on a Mercedes

Model: Mercedes Classe C W204 - Years 2007-2013
Part: Warning light – error code

The active hood system is designed to protect pedestrians in the event of a frontal impact: when sensors detect a collision with a pedestrian, the hood instantly lifts a few inches, creating space between the hood and the rigid engine components. This reduces the severity of the impact on the pedestrian's head. The main components are the pedestrian sensors mounted in the front bumper, one on the right and one on the left. They measure the acceleration and force of the impact on the bumper. In the case of the video, the left one was physically broken: Another component is the ECU that processes the sensor signals, and the pyrotechnic (or mechanical) actuators located near the hood hinges; when they receive the signal from the ECU, they explode like an airbag to lift the hood, which is designed with deformable areas to absorb energy. When the hood is activated, the system must then be reset, and the actuators must be replaced. If, as in the case of the video, the sensor is broken, the ECU detects the anomaly and triggers the error light.

Posted on 7 June 2026 by ScegliAuto

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How to Open a Stuck Boot on the Peugeot 407?

On the Peugeot 407, the boot may become stuck, possibly due to a problem with the control button or the lock actuator. In such cases, you can perform an emergency opening by following the simple procedure shown in this tutorial. First, open the rear doors, then lower the seat back by operating the release lever. Next, go inside the boot, locate the lock, and manually operate it using a flathead screwdriver. The boot will then be free to open.

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