In the final episode of the first series of the brilliant British police drama Luther, there are several points where people are found using phone tracking. Mark North is tracked, for example, by Ian Reed leading to the final confrontation.
Luther's phone is on as he both makes and receives calls during his attempt to stay hidden while he is a suspect and while he works out how to trap Reed for the murder.
Am I missing something? At no point did I see an attempt to find Luther via his phone. Why not?