[woeh]

The decision about what sensor to use is more easily made when one of the sensors provides no data, or clearly disturbed data. Like in case of fog, mud on a camera, pouring rain, etc.

My phone often signals me that I have to clean the lenses of my camera, so I'm sure it's possible to detect unreliable sensors. Sure, you have to decide on all sorts of tipping points, and in the end that is probably expensive to develop and the reason the sensors are dropped.

[simondotau]

If fog or rain is so intense that objects within a few feet of your car are obscured from vision, I'd suggest that maybe you shouldn't be operating the car at all, regardless of any assistance technologies it might possess.

[woeh]

True, that is good advice. I have been surprised by terrible rainshowers and fog before while already driving though.

[rjmunro]

My brother's Tesla signalled that the side cameras were faulty or needed cleaning when we drove down a country lane in the dark. This did not raise my confidence in the Autopilot system.