KF93

I have a 2015 GL350 with about 110k miles. Last year in January on a trip between California and Colorado I started having excessive brake fade and took it to an independent shop in Reno. They diagnosed it as a master brake cylinder and replaced that. Then in May I did the same drive again, starting having similar issues as well as the pre-safe system not available. The dealership in Colorado diagnosed it as the ESP module and replaced that. Module failed again with the same symptoms a few months later and my local dealership replaced the same module under warranty. Now I'm having the exact same symptoms only a few months later. Excessive brake fade- it goes all the way to the floor and I get the no cruise control and no pre-safe braking system error. Have an appointment with the dealership again but I'm worried they are going to tell me its the same part that's now been replaced twice. What could be the underlying issue that could cause the ESP module to fail three times in a year?