parking sensor problem after dead battery

[nikosf]

The battery full discharged. I turn on the engine with a charger. Then I recharged the battery. Since then the LED on PDC is on (flashing) when I put "R" or enable the PDC button the long continuous beep is heard (like when you are already too close to the object) even though there is nothing around the car...
after a second the sound disappears, but the sensors are not working.
I checked all sensors and they are OK
When I turn the key in position 2 turn on the PDC the light is steady green and the sensors are working.When I active a sensor, the sensors are not working and the ligth goes "flashing"
I didn't have any problem before the battery gone dead.
Maybe is a programming issue
What can I do to fix it?
I have read all posts about PDC problems
Thanks in advance

EDIT
The problem solved.
The dealer recoded the PDC