2013 Cadillac brake failure and how to fix this very dangerous problem ?

What is your question?

I have a Cadillac SRX- if I slide on ice , snow, or mud or gravel while braking my brake pedal pulses then it goes to the floor . My pedal remains spongy with little to no braking power. After the car sits awhile it seems to repair itself . It could repair itself in a couple hours or overnight . When you have this brake failure you have very little stopping power. Pedal is almost completely on the floor. I took it to Cadillac tech. My car was put on diagnostic. Mechanic called and said no codes to show any problems. Has anyone else had this problem ? What was done to repair this ?

What makes this problem better or worse?

Never sliding

How long has your 2013 Cadillac SRX had this problem?

On and off . Third time in 2 yrs