Normally, LabQuest 2 turns on in less than 90 seconds and displays the Meter screen (the screen that has the File and Sensors menus). If LabQuest 2 fails to start, follow the links below to diagnose the issue. Each link labeled with a TIL number, links to a document to help diagnose and repair each specific issue.

Screen flashes black and white
This is most likely a power or battery-related issue.
See: Why does LabQuest 2 screen flash white, and then black, when I turn it on?

Frozen on the logo screen
Either the LabQuest software needs to be re-installed, or the power button is stuck.
See:Why does my LabQuest 2 get stuck while booting and not make it past the logo screen?

Frozen on the blue screen
The LabQuest software needs to be re-installed.
See:LabQuest 2 software corruption recovery instructions

Screen stays black
This is a possible hardware problem.
See:My LabQuest 2 or LabQuest 3 won't turn on and the screen stays black.

See Also:
My LabQuest 2 asks for a Linux login. What should I do?
LabQuest 2 booted to a screen that lists LabQuest App and Audio Function Generator, but the LabQuest App will not open.
LabQuest 2 FAQs
LabQuest 2 screen is solid white, does not respond.