Definition - What does Yoyo Mode mean?
Yoyo mode refers to a situation wherein a computer or a similar device seems stuck in a loop -- turning on briefly, then turning off again. The idea is that the rapid restart and shut off patterns can be compared to the down and up cycles of a yoyo.
Techopedia explains Yoyo Mode
A “yoyo mode” situation can happen for various reasons, including battery problems, problems with the boot-up sequence, or other issues. This type of activity can be hard on the physical computer parts, including the fans, circuitry and power systems. IT professionals will have to analyze the physical device to determine why it is experiencing this kind of erratic loop.