2001 s500 when i start the car wipers come on and brakes also and will not turn off. i unplugged all the computers in the fuse boxes under the hood as instructed by a mechanic friend to maybe dry off the connectors to help the brake light problem but now wipers come on and stay on as well ?

I don't know what a SAM is. I do not have any manuals. I was thinking of getting on ALL DATA. Would ALL DATA have the info needed for most repairs?

You have posted numerous threads with numerous electrical errors , which indicate water damage , you could buy new front and rear SAMs but you will fry them
Again unless you pull up all carpeting and replace all the wiring harnesses and SAMs

I am an A&P mechanic and have always worked on my own cars but have come to realize the MB is a much more sophisticated automobile than I have ever attempted to repair. Thank you and everyone for all help so far.

I said this in another thread, but you really need XENTRY/DAS to work on this car. OBD code readers are next to useless...but with XENTRY you can talk to the SAMs, see the communication on the CANBUS, etc. Throwing parts at this car will get very, very expensive very quickly...