If the battery is low(alarm 2100), the battery must be replaced within six weeks. The battery is located at the bottom of the NCU box (see picture).
Battery type Order Number: 6FC5247-0AA06-0AA0
1. Switch off the machine.
2. Pull out the fan module with the battery (see figure), There is a latch on the lower side of the
slide-in module. Press this latch up and pull the slide-in module forwards and out at the same time.
3. Replace the battery(or Install the new slide-in module(, the battery(modul) must be replaced within 15 minutes, or the data will be lost!!!
4. Switch the controller on again, the battery alarm should now be off.