How many cubes are there?

A drunk phoned the police to report that thieves had broken in to his car.
"They've stolen the dashboard, steering wheel, break pedal, even the accelerator," he cried out.

However, before the police investigation could get under way the phone rang a second time, with the same voice came over the line. "Never mind," said the drunk with a hiccup, "I got in the backseat by mistake."