HELLO ALL

I have a massive problem, i was cleaning the interior of my car today, and then went to move it, when i turned the ignition the lights on the clocks ie air bag battery etc did not turn on

i then turned the engine over and the rev counter did not operate, now all well and said you would say piece of piss a fuse has gone!

well we checked all fuses, every relay etc and all working perfectly, i also took a reading for the battery and it was registering 11.86 at tickover, so the alternator is not charging the car and i was told by the rac who came to ASSIST but failed in the words of them

the light in the dash that displays the battery sends a message to the alternator to tell it to charge the battery!

can anyone help i am in MILTON KEYNES and urgently need help as i need to use this car daily and its not working PLEASE HELP