Before Servicing The Computer; Disabling The Built-In Battery; Removing The Micro Sim Card; Removing A Major Fru - Lenovo ThinkPad T550 Hardware Maintenance Manual

Before servicing the computer

Carefully read this topic before servicing the computer.

Disabling the built-in battery

Before replacing any FRU, ensure that you have disabled the built-in battery by doing the following:
1. Turn off your computer and disconnect the ac power adapter and all cables from the computer.
2. Turn on your computer. When the ThinkPad logo is displayed, immediately press F1 to enter ThinkPad
Setup.
3. Select Config ➙ Power. The Power submenu is displayed.
4. Select Disable built-in battery and press Enter.
5. Select Yes in the Setup Confirmation window. The built-in battery is disabled and the computer turns off
automatically. Wait three to five minutes to let the computer cool.

Removing the micro SIM card

For access, remove this FRU:
• "1010 Removable battery" on page 57
If the computer has a micro SIM card installed, you also must remove the micro SIM card before you
start the servicing.
After you finish the servicing, ensure that you install the micro SIM card (if available) into the micro SIM
card slot.

Removing a major FRU

This section provides instructions on how to remove a major FRU.
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