Have HVAC Questions? Ask an HVAC Expert for Answers
Is the fan still running on the outside unit?
Does it shut off if you turn the thermostat off?
OK you may have a bad thermostat or stuck relay on the unit outside causing the issue. I would disconnect the Red wire going to the thermostat and if it still runs then there is a stuck relay on the outside unit.
If you shut the breaker off to the AC and furnace nothing can run on it.