power-on self-test
nounUK /ˈpaʊər ɒn ˈself test/
US /ˈpaʊər ɑːn ˈself test/
A quick check a computer does when you turn it on to make sure its parts are working.
When you press the power button, the computer runs a power-on self-test before showing the screen.
RELATED WORDS
OTHER MEANINGS
2. A built-in test that a device runs by itself when it starts up.
The printer's power-on self-test showed that the ink was low.
3. The first step in starting a computer, before the operating system loads.
If the power-on self-test fails, the computer may beep to warn you.
4. A routine check that confirms a machine's basic parts are ready to use.
The technician watched the power-on self-test to see which part was broken.