How to change battery in your P2 housing 

Sign of a bad battery 

1. Remove the four screws on top of housing plate

2. Separate top plate from housing. Use a soft hammer to to tap the sides till free. Remove battery and replace with new.

3. Apply a thin layer of gasket sealer to the top of housing.

4. Put top housing plate back in place and tighten all four screws.

5. Plug P2 in. Reset screen by pressing and holding new activity until screen zeros out.