Mercedes: 380 SEL AC/Heater do not work at all, amp fuse, benzworld

Question
I can not get the AC or the Heater or blower to come on at all, replaced the 25 amp fuse to no avail. What could be the cause?

Answer
There may be a problem with the ignition switch. Or with the Heater blower blower control module.
I had to replace the electrical back end of my ignition switch as the internal contact stopped working.

I would post a specific questions to http://www.benzworld.org/forums and see what you discover.
Good Luck
Robert