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Remove the CMOS battery (CR2032)

Follow the instructions in this section to remove the CMOS battery.

About this task

The following notes describe information that you must consider when replacing the battery:

  • Lenovo has designed this product with your safety in mind. The lithium CMOS battery must be handled correctly to avoid possible danger. If you replace the CMOS battery, you must adhere to local ordinances or regulations for battery disposal.
  • If you replace the original lithium battery with a heavy-metal battery or a battery with heavy-metal components, be aware of the following environmental consideration. Batteries and accumulators that contain heavy metals must not be disposed of with normal domestic waste. They will be taken back free of charge by the manufacturer, distributor, or representative, to be recycled or disposed of in a proper manner.
  • After you replace the CMOS battery, you must reconfigure the server and reset the system date and time.
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 of 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.

The battery is a lithium ion battery. To avoid possible explosion, do not burn the battery. Exchange it only with the approved part. Recycle or discard the battery as instructed by local regulations.
  • Read Installation Guidelines and Safety inspection checklist to ensure that you work safely.

  • Power off the server and peripheral devices and disconnect the power cords and all external cables. See Power off the server.

  • Prevent exposure to static electricity, which might lead to system halt and loss of data, by keeping static-sensitive components in their static-protective packages until installation, and handling these devices with an electrostatic-discharge wrist strap or other grounding system.

  • If the server is installed in a rack, slide the server out on its rack slide rails to gain access to the top covers, or remove the server from the rack. See Remove the server from rails.


  1. Remove the front top cover. See Remove the front top cover.
  2. Locate the CMOS battery on the system board assembly.
    Figure 1. CMOS battery location
    CMOS battery location
  3. Open the battery clip as shown and carefully take the CMOS battery out of the socket.
    • Failing to remove the CMOS battery properly might damage the socket on the system board assembly. Any damage to the socket might require replacing the system board assembly.

    • Do not tilt or push the CMOS battery by using excessive force.

    Before you remove or install the CMOS battery from or into the socket, differentiate between the positive and negative ends.
    Figure 2. CMOS battery positive and negative ends
    CMOS battery positive and negative ends
    Figure 3. CMOS battery removal
    CMOS battery removal
    1. From the negative end, lever the CMOS battery from the socket with a slotted screwdriver.
    2. Remove the CMOS battery.

After you finish

  1. Install a replacement unit. See Install the CMOS battery (CR2032).

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

Demo video

Watch the procedure on YouTube