Disable Rom-Write Protection; Use A Usb Repair Shim To Diagnose And Fix Problems - Lenovo 100e Chromebook Hardware Maintenance Manual

Disable ROM-write protection

You need to disable the ROM-write protection function before you can use a repair shim to diagnose and fix
problems.
Step 1. Disconnect and the re-connect the battery cable.Refer to "" on page for how to locate and
disconnect the battery cable.
Step 2. Connect the Chromebook to ac power to activate the battery.
Step 3. Boot the Chromebook into Developer Mode.Refer to "Boot into Developer Mode" on page 23 for
instructions.
Step 4. Press ctrl —alt — →(F2) to display the virtual terminal.
Type root and press Enter to log in as root.
Step 5.
Step 6. Type the following command and press Enter at the command prompt.
flashrom –p host –wp-disable
Step 7. Type the following command and press Enter at the command prompt.
flashrom –p ec –wp-disable
Step 8. Press the Refresh key and the power button to restart the Chromebook.
The ROM-write protection is disable after restart.

Use a USB repair shim to diagnose and fix problems

Make sure the ROM-write protection has been disabled. Refer to "Disable ROM-write protection" on page 24
for instructions.
Step 1. While holding down the esc and the refresh key
recovery screen should be displayed.
Step 2. Connect the USB repair shim to the computer. The repair shim will update the computer firmware
and OS image automatically.
Step 3. When prompted, choose I to install the shim image to the computer.When the update is completed,
the computer restarts to the factory-test-image environment and then starts the Final Function Test
(FFT). The FFT will run for 10 minutes and then the Final Assembly Test (FAT) will start.
Note: When computer restarts, remove the repair shim and put it in a safe place.
Step 4. If the Vital Product Data (VPD) is displayed on the screen, press esc to continue.
If the system board is replaced, you are required to enter the VPD.
Note: The VPD is a 20 — character string.
Table 1. Combination of the 20 – character VPD
Preceding
characters
"1S", 2 digits
The MTM and SN can be found on the label attaching to the bottom cover.
Step 5. Follow the instructions on the screen to start the Final Function Test (FFT).
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Hardware Maintenance Manual
Machine type
7 digits
, press the power button.The Chrome OS
Model number
3 digits
SN
8 digits