Remote locking dead!

My remote locking has died after a flat car battery. The car was jump started and fired up fine. However, since this the remote locking doesn't work (worked just before it was jumped). The remote battery is fine (new battery tried and second key tried) however no response from the car. So no alarm or locking, but the central locking is working via using the key in the lock. Anybody got any ideas (fuses have been checked and replaced) as I suspect either the receiver (new one will need coding, expensive) or the alarm ecu unit. But the only way to I think I can find out is via an Alfa dealer and plugging the car onto their machine.

i am waiting delivery of new alarm ecu because of the same reason. and you are right, dealers machine will help to find out that there is an error in alarm ecu and they will kindly offer to order new one. but if i am not mistaken, there are two devices, one is in the right side of trunk, there is also the key for switching alarm on/off, this is alarm ecu, and other is at the receiver ecu, it is located in rear shelf, you can reach it also from trunk. the main problem is dealres cannot say with is defected, they only see a mistake in system. I will start with receiver ecu.