EXC_BREAKPOINT crash

I have this setup with a navigationcontroller:

SlideMenuController -> SchedulesViewController -> Schedule ViewController -> IntervalView

The schedulesviewcontroller is a list of all the schedules. The Schedule ViewController is the view with information about a schedule. IntervalView is the viewcontroller with a custom pickerview selecting a value.

I can load the SchedulesViewController, and then go to the ScheduleViewcontroller, and also from there to the IntervalView.

But when I try to hit the "Back" button, it works to the Schedule ViewController, but when I want to go back to the "SchedulesViewController", it crashes

[IntervalView respondsToSelector:]: message sent to deallocated instance 0x7fc78d320dc0

Thread 1 > EXC_BREAKPOINT(code=EXC_I386_BPT)

I don't know what code to show you, any help would be appreciated.