When driving in the rain, the vehicle flashed a collision warning indicator and applied the brakes as if there was an imminent collision with an object ahead, but the street ahead was completely empty - no vehicles or other objects that would warrant deploying the pre-collision braking system were present. If there were a vehicle behind me at the time, it is likely that their safety would have been put at risk when my vehicle suddenly started braking strongly for no apparent reason. The vehicle has been inspected by a Subaru dealership, who could not identify any issue. The dealer attempted to apply a software update to the EyeSight camera system that controls pre-collision braking, but was unable to apply the update. It is my belief that the camera-based EyeSight system interpreted rain on the windscreen as an obstacle and erroneously deployed pre-collision braking when there was no actual hazard ahead.
NHTSA ODI 11742331