What controls the central locking system?????

Does the battery run the unit?

Stupid question you may ask!! But I pressed on the remote central locking key, the locking system made a funny "buzzing" noise and the door lock wouldn't open.

I thought it must have been playing up. I disarmed the imobilizer using the fog key. I always leave the key in the "on" position and make sure the fault light disapears before starting the car. The fault light disapeared as usual. When I tried turning the key, the car would not fire up, I could see the the lights on the dashboard where fading, the longer I left the key turning.

I waited for at least a minute and tried again, it would not start up...... I kept on holding the the key and walaa, just like magic, it started.

What could have caused the problem