Most controllers switch using a basic open collector circuit. An internal transistor is switched on by applying a forward biasing signal to the base emitter circuit. When the transistor base is forward biased the transistor is switched on allowing current to flow from the collector across the junction to the emitter and to ground or battery negative, usually through a current limiting resistor.
Now as the transistor is switching an inductive load it will experience high back emf which depending on the loads inductance and speed of switching can destroy the transistor (e=-Ldi/dt) hence a freewheel diode is placed in parallel to the inductive load to prevent the transistor seeing this high voltage. The most common failure mode is for the diode to fail which in turn causes the transistor to fail.
So identify the switching transistor on the board, test and if faulty replace it AND the freewheel diode, otherwise it WILL fail again