Working fridge, warm freezer.

The fresh food compartment is cooled by air being blown from the freezer compartment into the fresh food compartment.

There is a panel, or door if you will, that separates the freezer and fresh food compartments. The freezer temp control determines how much cold air is allowed to escape into the fresh food compartment by opening or closing this panel.

In your case, the door must be stuck all the way open, allowing all the cold air to be diverted into the fresh food compartment. The compressor cycle is controlled by the thermostat in the fresh food compartment and thus 'short cycles' because the fresh food compartment acheives normal temperature while the freezer is relativel warm.

If the panel is restricted from moving (stuck in the extreme open position, for example), the fresh food compartment will get VERY cold while the freezer will be warm.

Try thoroughly defrosting the refrigerator. Possibly an accumulation of ice is preventing the panel from moving and/or is diverting all the cold air from the freezer into the fresh food compartment. It's a free fix and may solve your problem altogether.

If that doesn't help, or helps only temporarily, you may have a problem with panel/door/flap itself or the linkage that connects it to the control mechanism. Unless you're skilled in appliance repair, checking and repairing these components will require the help of a service technician

Hope this was helpful. Good Luck.