Would mineral deposits be sufficiently large and conductive that they would cause an actual issue between components?
They would probably represent nothing more than minor stray resistance/capacitance.
Assuming it was conductive enough, a scales bridge between higher voltage parts would just represent a path of material a few microns thick that would vaporize as soon as the toaster would be plugged in.
For other electronic devices, any component with a hole, like a microphone, barometric, humidity sensor, or mechanical (HDD), is more likely to suffer a more permanent fate. If water gets inside a relay housing, chemicals from the washing liquid may damage or gunk the contacts and reduce their life. LCD screens, glued parts and thin plastics don't fare well in dishwashers either...
>Would mineral deposits be sufficiently large and conductive that they would cause an actual issue between components?
A good proportion of water-damaged cellphones can be revived just by washing the logic board thoroughly in isopropyl alcohol. It's possible that this is due to small amounts of water trapped in crevices, but I've seen it work on boards that looked bone-dry under the microscope.
A lot of household appliances use potted relays and conformal coatings. If you pull the control board out of your clothes washer you'll see what I mean. It's particularly important because the control board is often within spitting distance of a solenoid that's holding back 60-80 psi of water.
They would probably represent nothing more than minor stray resistance/capacitance.
Assuming it was conductive enough, a scales bridge between higher voltage parts would just represent a path of material a few microns thick that would vaporize as soon as the toaster would be plugged in.
For other electronic devices, any component with a hole, like a microphone, barometric, humidity sensor, or mechanical (HDD), is more likely to suffer a more permanent fate. If water gets inside a relay housing, chemicals from the washing liquid may damage or gunk the contacts and reduce their life. LCD screens, glued parts and thin plastics don't fare well in dishwashers either...