will not start sometimes. keyfob will not operate. alarm is flashing while door on 2006 Jaguar XK8

does not show up on diagnostic code. no power to roof trunk or fob. tried to disconnect battrey and reconnect but still no start. looks like an alarm problem

Asked by for the 2006 Jaguar XK8
is your battery fully charge and clean terminal connection? after market alarm can sometimes lock up the ignition system thats an electrical problem.