I need help regarding a2 controller i accidently touched battery positive terminal to A2 led module while s1000 and battery ground cable connected .. and led module got fried .. i ordered new led module and pmu unit but still no luck connecting a2 to the PC .. please help

First take everything off the copter then connect the PMU to a power source then check voltage out if that is good then connect the A2 to the PMU via can 1.  Check power on any of the F connectors at the center pin and the positive pin if you have power connect the IMU to can 2. Check power again at any of the F connectors if you see power out, try connecting to the controller via PC.  If still no luck the programmable I/O circuitry is bad.  Programmable controllers work on two planes, intelligent (programmable) I/O and controlled power.  The optical I/O couplers at the board level are linked to triacs that often fail when power is reversed or an arc causes the voltage to go near infinity (E=IxR) where R goes to near infinity.   Good luck

So you are saying i need to buy a new A2 controller unit module ?

Probably...  You can buy only the A2 for about $405.00 US from Troy Built Models