Check engine flashing P0748 code?

Hello,

When you hit the rock did it dent the transmission pan? If so, this can restrict the flow of transmission fluid to the filter or pick up tube which will cause the code P0748 Pressure Control Solenoid A. I would raise the car up and inspect the transmission pan.

Here is a guide to help:

https://www.2carpros.com/articles/jack-up-and-lift-your-car-safely

Please go over this guide and report back.