Xsara hdi no power from battary

[DaveW]

My vtr hdi seems to have no power from the battary at all when the car is swtiched off, so the interior lights,clock, central locking dont work but however they do when the car is running or the key is at acc 2, i dont even get anything when the key is at acc 1! no idea where to even start looking for the problem any ideas/help please?