Switching from X11 to console suspends display

When using CTRL+ALT+F1…F5 which typically allows you to switch to console mode from an X11 session, the display suspends itself. Additionally, if booted directly into console mode and then starting an X11 application with xinit, subsequently shutting down the X11 application or attempting to switch console also ends up suspending the terminal. Does anyone know what’s causing this or how to fix it?

I’ve also been trying like mad to turn off framebuffer console, but it keeps enabling regardless of what kernel settings I put in extlinux.conf (nofb, nomodeset, etc.).

Which version of L4T?

Is it correct that your monitor uses anything other than 15-pin D-sub connector? The use of a D-sub implies monitor query is not possible. Other types (like DVI or HDMI or DisplayPort) work with monitor query.

There have been some issues with properly reading the EDID of the monitor (the monitor’s reply to query about its capabilities). You may be running into this issue, sometimes caused by software on the Jetson, sometimes caused by the monitor. Different software does this query in different places, e.g., X11 and console do their own thing, having one fail or succeed isn’t an indicator of what the other will do. This isn’t directly about your question, but may be of interest:
https://devtalk.nvidia.com/default/topic/933221/jetson-tx1/changing-the-refresh-rate-of-the-monitor/post/4888014/#4888014

If you are running R24.1, you may be running into this:
https://devtalk.nvidia.com/default/topic/946129/jetson-tx1/switching-to-tty1-6-/

We are using straight HDMI. I believe we are running into that same bug, which I found after posting this. Bugs, bugs and more bugs…