Caution: If you do a renew twice, without using the chip on the
lamp, you won't see the long flash either but it will be still
operational.
Replace Battery
Read this chapter carefully before replacing the battery.
Safety warning
Leaky or damaged batteries might cause cauterisation when in
contact with the skin; therfore use suitable protective gloves.
Open battery tray
Open the battery tray by pushing the locker to the middle of the
device like illustrated with the yellow arrow and pull out the tray in
the direction shown with the red arrow.