NHTSA Complaint #11530027 — 2022 FORD EXPEDITION

My Expedition has adaptive cruise control. I was driving on the interstate at around 65 mph with the adaptive cruise set. I was raining, so I set it to max range. It worked fine for the first few minutes of rain. As cars started to slow down, mine sped up and put me in an extremis situation where I had to forcibly apply the brakes. It was following the car in front of mine fine at around 55 mph, but then sped up despite the car getting closer as if there wasn't a car there. Only after I applied the brakes did I start getting an error that adaptive cruise and collision assist were not working due to a sensor being blocked. I've driven in rain many times and have never had this error. As far as I can tell the forward sensor failed due to moisture and instead of the adaptive cruise turning off, it actually caused the vehicle to accelerate since cruise was set to 65 mph. Sensor failed in a 5 minute rain storm. Software design does not fail safe, but rather the opposite.