Henry, best try googling for what you're after, try EC135 engineering manual, operation manual, flight manual etc, good luck. The diagrams posted some while back on here are the best that are generally available unless you're a bona-fide paying customer of the manufacturer with a need to have something better.
It's a fairly simple system if and it's a big IF, you've attended the manufacturers conversion to type and had many hours reading the manuals and a few years discussing faults as they occur with the engineers. Trying to explain it to those who are new on here from a standing start is akin to platting fog......