won't start!!

[paulw]

We have a '95' 306 N plate since garage sorted the airbag light, (corroded terminals under seat) We have a battery drain, but also management light is on, keypad won't recognise the code, car turns over but won't start. Always been a good started/runner. tried cleaning earth points. Is there a quick fix to by pass the key pad or to just get it running again? Been off road for about a year, but kept starting up to running temp.
thanks