When I got my hands on this Toshiba Chromebook 2 (CB35-B3340) its primary screen was cracked and unreadable. I was happy when I discovered I could use it as a Chromebox by an external HDMI monitor, but I quickly found the limitation of that approach when I tried to switch the device into developer mode: those screens were only visible on the screen I couldn't read.

Google has published instructions for putting a Chromebook into developer mode, but they weren't specific enough for use with an unreadable screen. It doesn't say how many menus are involved, and it doesn't say how much time to expect between events. Probably because these details vary from device to device and not suitable for a general document.

I looked around online for information from other sources and didn't find enough to help me navigate the procedure. Most irritating are the sites that say things like: "And from this point just follow the on screen prompts" when the whole point was I couldn't read those prompts at the time.

Now that I've installed a replacement screen, I can see what happens and more importantly, I can now document the information I wished I was able to find several weeks ago. The most surprising part to me was that it took roughly seven minutes to transition into developer mode, but less than a minute to transition out of it. Since all user data are erased in both of these transitions, I'm curious why the times are so different.

In any case, I've captured the process on video (embedded below) and here is the timeline for putting a Toshiba Chromebook 2 into developer mode even if the screen is not readable. Times are in (minutes:seconds)

  • Preparation: power down the device.
  • (0:00) While holding down [ESC] + [REFRESH], press [POWER].
  • (0:15) Press [CONTROL] + [D] to enter developer mode
  • (0:25) Press [ENTER] to confirm
  • (0:36) Press [CONTROL] + [D] to confirm
  • (6:52) Two beeps warning user the Chromebook is in developer mode.
  • (7:25) Chrome OS booted up into developer mode and ready to be mirrored to external monitor.

Following power-ups while in developer mode:

  • (0:00) [POWER] button as normal (no other keys needed)
  • (0:10) Press [CONTROL] + [D] to bypass 30-second developer mode warning screen, also skipping the two beeps.
  • (0:20) Chrome OS booted up into developer mode and ready to be mirrored to external monitor.

Exiting Developer Mode:

  • Preparation: power down the device.
  • (0:00) [POWER] button as normal
  • (0:08) Press [SPACE] to re-enable OS verification.
  • (0:15) Press [ENTER] to confirm
  • (0:48) Chrome OS booted up into normal mode and ready to be mirrored to external monitor.

https://youtu.be/iozVstbEGyc