TruckGuy 94

I have a 2011 GMC Sierra Denali with a park assist problem I’m hoping someone can help me solve. A couple months ago, I started getting a sporadic “park assist blocked” error. This is pretty common as the sensors are covered in snow in the winter. However, I then noticed the sensors began to work sporadically even if they were clear. A month or so after that, the message changed to “service park assist” and the system automatically disables itself. The button on the dash shows the system is off all the time and when I try to turn it back on, the orange light flashes for two seconds but then disables itself again. I’ve checked the fuse and unplugged the battery but have not been able to get it to reset. Does this seem like a sensor issue or a control module? Any ideas for next steps? Unfortunately since the system is disabled all the time I can’t check to see if one sensor is malfunctioning as I’ve read about on other forums. Update: when I started my truck once this week it randomly worked for 10 seconds then disabled itself again and hasn’t worked since.