Brought my Makita 6012HD 9.6V battery drill back to life!
As with most NiCds of this vintage the 9.6V battery pack will not accept a charge.
I have a Odyssey PC680 car battery lying around from a Subaru WRX, it’s still in OK condition so …decided to hard wire the Makita to run off the battery.

The construction of the battery pack is peculiar and…it has three terminals? I figured the third one was for temperature overload protection because there is a thermal sensor in the pack itself, don’t need that so pulled it out and soldered the alligator clip leads directly onto the + and – terminals at the top of the battery pack. Works great…this will be my countersinking drill – one less bit change.

Anyway…was using the drill and when I went to put it down on the bench I noticed the pos clip was hanging free !!!…crikey…the drill is working and it’s not connected to the car battery!!! The car battery has been charging the battery pack in the drill, and doing a good job because she has plenty of power!
Went back to check that thermal sensor that I pulled out and it’s actually a thermal fuse and yes – open circuit.
Looks like the “dead” battery pack is taking a charge, I need to pull everything apart again including the charger and re-wire as needed and hopefully the charger will once again be able to charge the battery pack.