I just got a new 15.6 V craftsman drill and noticed that when charging the nicd batteries, the do *not* get warm at all, but in the instructions, it says the batteries do get warm. They seem to be charged, but then they already had juice in them when I charged them for the first time, so I'm not completely sure the batteries are charging. Is there a way I can check the charger? I have a multimeter, if that helps. Thanks.