You may wanna have a look at "PIC 767" or somesuch by a publisher called Wilco. It´s an addon for the Microsoft FS2002, and from what I´ve heard it´s a very, very good addon as far as simulated systems (and their failures) are concerned.
I´ll try to dig up a link to it so you can check it out for yourself.
Ah okay, I found two links to reviews of this product. Looks like it is just what you´ve been looking for.
Here are the links:
http://www.simradar.com/reviews/72/7...n_Command.html
http://www.avsim.com/pages/0301/767pic/pic.html