The BIOS backup battery is installed ex works and must be replaced every 5 years. See accessories for type number.

Procedure:

  1. Assure protection against electrostatic discharge (ESD).
  1. Disconnect device from power.
  1. Unscrew 6 screws on the base plant (T20) and carefully remove the base plate.
  1. Disconnect the ribbon cable on the SSD (not on the motherboard).
  1. Remove the battery from the housing wall.
  1. Remove the remaining Velcro strips from the housing wall.
  1. Unplug the old battery.
  1. Carefully install the new battery (The realtime clock information is lost after 30 seconds without power).
    In this case, plug in the WAN cable at start up for the device to acquire the time from the Internet).
  1. Attach the new battery with the new Velcro strip to the housing wall.
  1. Plug in the ribbon cable on the SSD.
  1. Reinstall the base plate (maximum torque: 5 Nm / 3.7 lbf ft).