Chrysler Grand Voyager - Replaced battery and now alarm wont switch off and - lancashire lad

Hi guys,

I need your help once again to get me back on the road.

My 2002 Grand Voyager has been stood for a good few weeks over the Christmas and New Year period and i recently went start her up and take her for a drive but the battery was so flat there wasn't even a faint light on anywhere.

so i removed the battery and took indoors and placed on charge for 24 hours, then fitted back onto the car, this is where the fun starts.........

on reconnecting the battery the alarm armed itself and within a few seconds went off as the bonnet / hood was open but no ammount of key fob pressing turned it off, it only locked and unlocked the doors. i tried to put my key in the ignition whilst the alarm was sounding but it wouldnt start and oddly all the gear indicator lights where lit up (PRND3L).

i'm guessing that my car has lost its pairing with my coded key or something along those lines but may be wrong.

do i need to pair my key with ECU again? i know in the past on other cars you do can similar things like put in the door and hold to unlock for a few mins or put in ignition and press lock / unlock in a certain sequence.

Hopefully someone will have had this before and knows how to reprogram the key,ecu,bcm.........

thanks in advance Scott.