Peugeot 106 diesel has been stood for about 4 months, wont start changed battery, no power at all to the car ?

Peugeot 106 was in a side impact accident and has been stood for about 4 months. after the accident it drove fine we have changed the battery but when keys are in ignition there is nothing no power at all to the car pls help Peugeot 106 diesel has been stood for about 4 months, wont start changed battery, no power at all to the car ?you might need to check the cables and the connection Something could have come loose. Also go be to your battery connections and clean them and the cables real good