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Remove the CMOS batteries (CR2032)

See this topic to learn how to remove the CMOS batteries.

About this task

To avoid potential danger, make sure to read the following safety information.

disconnect all power
The power-control button on the device and the power switch on the power supply do not turn off the electrical current supplied to the device. The device also might have more than one power cord. To remove all electrical current from the device, ensure that all power cords are disconnected from the power source.

When replacing the lithium battery, use only Lenovo specified part number or an equivalent type battery recommended by the manufacturer. If your system has a module containing a lithium battery, replace it only with the same module type made by the same manufacturer. The battery contains lithium and can explode if not properly used, handled, or disposed of.

Do not:
  • Throw or immerse into water
  • Heat to more than 100°C (212°F)
  • Repair or disassemble

Dispose of the battery as required by local ordinances or regulations.

Consider the following when replacing the battery.
  • Remove the CMOS battery will cause system lockdown. To unlock the system, contact Lenovo Support.

  • Lenovo has designed this product with user safety in mind. The lithium battery must be handled properly to avoid potential danger. Make sure to follow instructions in this topic while replacing the battery.

  • The CMOS battery must be replaced with another unit of the same type (CR2032).
  • For high temperature operation environment, it is recommended to use CR2032HR instead.
  • After replacement is completed, it is required to reconfigure the server and reset the system date and time.
  • Dispose of the battery as required by local ordinances or regulations.


  1. Make preparations for this task.
    1. If applicable, remove the security bezel (see Remove the security bezel).

    2. Remove the top covers (see Remove the top covers).

  2. Proceed to the section corresponding to the CMOS battery to be removed:
    Figure 1. CMOS battery locations on the system board

    1 security battery for ThinkShield2 System battery

Remove the security battery


  1. Remove the fan cage assembly (see Remove the fan cage assembly).
  2. Gently press on the nub on the side of the CMOS battery as illustrated; then, pivot the battery away from the seat to remove it.
    • Avoid excessive force on the CMOS battery, as it might damage the socket on the system board and result in system board replacement.
    • When the security battery is removed, ThinkEdge Security Pack Enabled enters lockdown mode, while activation is required before booting up the system.
    Figure 2. Removing the ThinkShield battery

Remove the system battery


  1. Remove PCIe riser 2 (see Remove the PCIe riser assemblies and adapters).
  2. Open and hold the retaining latch; then, pivot the battery toward the positive (+) side to disengage and remove it from the seat.
    Figure 3. Removing the system battery

After this task is completed

>Watch the procedure on YouTube.