See also:

Checking settings
The current Collision Warning settings can be checked by pressing MY CAR on the center console control panel and going to Settings Car settings Driver support systems Collision Warning. ...

Limitations
Distance Alert uses the same radar sensor used by Adaptive Cruise Control and the Collision Warning system. See page 159 for more information on the radar sensor’s limitations. NOTE Strong sun ...

The radar sensor and its limitations
In addition to being used by ACC, the radar sensor is also used by Distance Alert (see page 164) and Collision Warning with Full Auto-brake and Pedestrian Detection (see page 172). This sensor ...