Cycling the switch should have no effect on a leak. Every time you turn the engine off, the system equalizes between the high and low sides. It probably just got low enough again for the low pressure switch to shut it down. You can sometimes find the leak by looking at the lines and joints and find where the greasy spot is (if you keep your engine otherwise clean). The oil in the refrigerant grabs dust and leaves a greasy spot at the leak site.