Step 2
Take notes using your paper and pencil as to how the batteries are positioned in the Makita battery pack case. This will assist you in the later reassembly of the Makita battery pack.
Step 3
Use the battery tester to determine which of these batteries needs to be replaced. Test each individual battery and mark the batteries to be replaced.
Step 4
Purchase similar-voltage rechargeable batteries at a local hardware or electronics store. For example, nickel cadmium (NiCad) batteries should be replaced only with new NiCad batteries.
Step 5
De-solder the first "bad" battery, taking note of how it is positioned in the chain. The new battery will need to be placed in a position so that its polarity matches the original battery.
Step 6
Re-solder the new battery into the chain.
Step 7
Repeat this process with each individual "dead" rechargeable battery cell within the Makita battery pack.
Step 8
Place the link of batteries back into the Makita battery pack and screw the case closed.
Step 9
Place the newly repaired Makita battery pack on the battery charger overnight.