Note: I was fairly sure that I had not disconnected the connector from the "hood closed?"-switch... So the previous owner had pulled it. That switch, if not pressed (i.e. when bonnet open) is electrically closed, and electrically open when the bonnet is closed. Thus, when the plug is pulled, the bonnets "seems" to be closed always. Thus, with the bonnet open, and the plug pulled, the car can be locked, but with the plug connected, the car can only be locked, when the bonnet is closed...