There isn't even a real consensus with respect to the cause of the either the last major ice age, or the little mini ice age in the second millennium AD. People have pegged everything from solar activity to ocean currents to subtle shifts in the earth's tilt or orbit of the Sun. Until someone knows conclusively what cause the last ice age(s), they won't have ANY idea when the next one is coming.
It’s not a question of prediction. Climate records are still being set right now. After a look on the Web of Science Journal Database, which I would encourage someone with free time to check out the journal articles there. There’s still measuring experiments on various aspects of global climate going on in the past five years (recent for publication history). But regardless of whether ice age or a prolonged interglacial happens, we actually are recording the Earth’s climate, and actually have the tools to do so. I hope there’s time before a real ice age, because an ice age is a true killer of the food supply, just take a look at what happened to the Norse, or much of Europe when they lost their years of golden sunshine. There was something that drove them to colonize tropical America.