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My DIY designed green house watering controller (PIC24FV32KA302) has worked pretty good over the years , but last Friday, its LCD was blank …. seems my design was missing a vital component .. A fuse ! … the 12v pump had seized ( impeller was blocked ) when the timer fired up the IO pin the 12v battery dumped all its amps through the MOSFET and shorted the pumps winding ,as the pump is underwater it didn’t burst into flames. This destruction condition lasted till the switch died … Pump was about 150 Ohms, but finished up about one ! The drive circuit similar to this ! Lesson learned..