I drove on Autopilot on the A14 through the new A1/Cambridge section yesterday & the car started to brake heavily from 72 mph at one point, virtually an emergency stop. Luckily nothing was following & I took control almost instantly. The sky was grey & I wasn't driving under anything so no shadows, straight piece of road, one car a long way in front & nothing visible in the rear view mirror.
Google maps navigation showed the new road correctly so I can only assume that the car somehow picked up a former road (or a tiny bit from a construction contraflow) in its path at that point. On other roads I occasionally notice that the speed symbol on the screen is different to the actual road.
It begs the question - what does Tesla actually use to determine a roads' speed?
This was part of a mammoth journey from Chester via M6/A14 to assist my Father (outdoors) near Bury-St-Edmunds, supercharging at Elveden for the return - around 11 hours driving including the supercharger stop.
At one point near the Gravelly Hill Interchange when using Autopilot/Autosteer in heavy traffic the moving graphic display locked up & Autopilot disengaged for a couple of minutes - looked like the car lost sight of the lane lines so my car and those around remained static on the screen for about 1/2 mile even after the traffic spread out and we moved on. It then corrected, I switched back to Autopilot & everything was fine. I hope that's a one-off.
.....It's made me much more wary about these sort of things happening when using Autopilot.
(if anyone here driving a blue LR, followed by a blue M3P passed a white LR, M6 near Coventry yesterday morning, that was me!)