💬 Magic Smoke
The joke name for the smoke that comes out of an electronic component when it fails — with the running gag that a device only works while the smoke is still inside it.
If you see or smell it, disconnect the battery straight away and find out what caused it before plugging anything else in. Something failed, and the cause is often a short or a wiring mistake that will kill the next part too.
What it actually does
A running joke with a real meaning: electronics are said to run on magic smoke, and once you let it out they stop working. Saying you released the magic smoke means you have destroyed something electrical, usually visibly.
In practice
The usual causes are entirely diagnosable — a short from a chafed wire, reversed polarity, over-volting a component, or an ESC asked for more current than it was rated for. The smoke is the symptom; the wiring or the setup is the cause.
Worth knowing
Before replacing the part, find out why it failed. Fitting a new ESC to the same short circuit is an expensive way to make the same smoke twice.