BEFORE you put the Chromebook into developer mode, the Read/Write screw must be removed from the motherboard. See pictures below.

Picture 4.1

Get to developer mode: Samsung Chromebook XE303C12

On this device, both the recovery button and the dev-switch have been virtualized. Our partners don't really like physical switches - they cost money, take up space on the motherboard, and require holes in the case.

To invoke Recovery mode:

• • Plug the DC Power in

• • Hold down the Esc + Refresh + Power until the display turns on then release.

  • At the screen that says the “Chrome OS is missing or damaged”, press Ctrl + D then Enter.

  • At the screen that says “Chrome OS verification is turned off”, press Ctrl + D, the device will restart and progress into developer mode.

  • Do not touch or do anything for 3-5 minutes until it progresses back to the “Chrome OS verification is turned off” screen, then press Ctrl + D

  • Wait until the device boots to the Chrome start screen, Press Ctrl + Alt + → (Ctrl-Alt-F2)

Once in the command prompt continue to the next page, if not in a command prompt retry the above steps.

Once in developer mode: Samsung Chromebook XE303C12

***New Update, 8/22/17: With the new firmware update on chromebooks, We have to work around an issue with the / symbol.

When changing the serial number on devices with "Product_S/N" stored in the VPD table, and VPD not allowing techs to change "Product_S/N" due to the [/] character, the devs have confirmed that the best solution is to deleted "Product_S/N" entirely, using the <vpd -d > command. Then, place what WOULD be the "Product_S/N" value under the "serial_number" key. The process below is updated for this issue.

Type as shown below, if it’s Capital leave it Capital, if its lowercase leave it lowercase. Spaces are important make sure if there is a space you type it in the terminal.

• • Type: chronos

    • Press Enter

  • Type: sudo su

    • Space after “sudo”.

    • Press Enter

  • Type: vpd -l (lowercase L)

    • Space after “vpd”.

    • Once you type vpd -l, this will display the current motherboards information including the motherboards current serial number.

    • Press Enter

  • Type: vpd -s “serial_number”=”0000000000X”

    • Replace the 000’s with the Device Serial number from the original device

    • The Last letter of the serial number you will leave off, with the new update "Serial_Number" needs to have the info that "Product_S/N" would have had.

    • Space after “vpd”, Space after “-s”.

    • Make sure the serial number is CAPITAL letters.

    • Press Enter

    • If flashromPartialWrite() error displays make sure that the read/write screws have been properly removed. See Picture 4.1.

  • Type: vpd -d “Product_S/N”

    • Space after “vpd”, Space after “-d”.

    • Press Enter

  • Type: dump_vpd_log --force

    • Space after “dump_vpd_log”.

    • Press Enter

  • Type: dump_vpd_log --full --stdout

    • Space after “dump_vpd_log”, Space after “--full”.

    • Press Enter

  • To close the command line session, type EXIT to close shell and EXIT to close the terminal.

• Leave the device in developer mode once the repair is completed, so that the QC Team can Verify the SN Change.