Power Steering Failed problems of the 2013 Cadillac ATS

Vehicle stalled quietly when coming to stop with vehicle in neutral and/or clutch depressed. I say quietly because I did not hear or feel it shut off. (different from stalling vehicle due to improper foot work on the clutch) when I went to turn left I realized it was dead. Vehicle did restart immediately. This has happened 6 - 10 times in the last 3 months. Most recently the power steering rack failed to turn back on at restart. Dealer serviced steering controller per TSB. They could not duplicate random stalling in a 10 mile test drive as it only happens to me only once a week or two. This could be more dangerous if it did not restart and I was in the middle of an intersection or moving.

I have two issues to report that may be a safety concern: 1) there have been multiple times when driving in wet conditions (rain/snow) where I will get a 'power steering failure' warning. When this happens the power steering does one of two things. It either almost locks up and becomes extremely hard to turn the wheel, or it will still move easily, but it won't auto center when making turns. I have reported this to the dealer and they said it was a bad steering angle sensor. They replaced the sensor but the issue is not resolved and now that it's snowing it's happening more and more consistently. 2) there have been 3 cases where I was driving and coming to a stop and the car will just randomly shut down. I lose all ability to steer (since it's electric steering) and brake. This stall is different then a stall associated misuse of the clutch. The clutch has been pressed in all the way in when this happens and the car doesn't shutter like a clutch stall, just totally shuts down quietly. Luckily there has not been an accident yet, but if this happens when there are multiple cars around me it will be difficulty to avoid one.