Mitel 3300 Technician's Handbook page 211

- Lift the clip that holds the battery in place with the index finger of
one hand
CAUTION: Lift the clip just enough to slide the battery out.
Forcing the clip up too far could cause damage requiring
replacement of the entire assembly.
- Pry up the battery and slide it out from its holder as shown in
Figure 54.
3. Install the new battery with "+" sign facing up towards you.
- Lift the clip
- Slide the battery into the coin cell holder.
4. Replace the controller cover.
Figure 68: Removing the Battery
Install and Replace Units
201