Yes, all functions work fine except for the battery pull down problem.
If I pull the battery real quick and test it, it's not down for
voltage much and recovers to full voltage in a few minutes so maybe
the battery state LED display is just haywire.
This sounds like normal behavior from a dying battery. NiCad, NiMH and
alkaine batteries all act this way.
Since it works for a few seconds, it's likely that the batteries have not
shorted or leaked. I built a good deep cycle discharger from a five volt
relay and a large (10 Ohm 10watt) resistor. The relay coil was in parallel
with the resistor, and it's contacts when activated connect them to the
A push button across the contacts to activate it and an LED with a current
limiting resistor completed the device.
You push the button and let the battery discharge. When the voltage gets
to low to keep the relay closed, it stops discharging but the battery does
not go too low to be damaged.
If it is a NiCad or NiMH battery a few charge discharge cycles should
bring it back to normal. This assumes that the batteries have not leaked
or been damaged in any other way.
Note that this should NEVER be done to lead-acid or Lithium batteries.
While many experts have claimed that NiCad and NiMH batteries do not
have a memory effect, I used to get lots of NiMH batteries or cell
phones as gifts when they were near dead. A few cycles in the reconditioner
and they were back to normal.
This is almost seven years later, and I'm still splitting the packs apart
and using them to rebuild ham radio battery packs.
Lithium Ion battery packs can be "fixed" by sitting overnight in a freezer,
but it has NEVER worked for me. Freezing ultrasonicly welded NiCad packs
makes them easy to split open and replace the batteries.