Thanks for response. I will try to follow your instructions, however I cannot check during charging as you suggest, because it will not initiate the charging process. The pdf link you provided is the one I have been following. As soon as I start the charging process by pressing and holding start/enter button for two seconds, the readout says BATTERY CHECK WAIT…, then I get the CONNECTION BREAK, a loud beep, and it will not charge. Pressing Inc button at that point does nothing. I have to press stop button to start all over.
The manufacturer of the charger is different from pdf, but I assume they operate the same. The charger in the pdf is Redox Beta and mine is a imax B6.
I have purchased several more batteries and external chargers to charge batteries separately and place in robot to see what happens. So far, the first set of externally charged batteries I placed in robot drained almost immediately. I have some more batteries arriving today with 2 more external chargers to try out. I will charge the new batteries as well as original batteries that came with these chargers and I think these chargers have feature to indicate voltage on cells. The two new chargers are XTAR, same as batteries that came with robot. I will test these freshly charged batteries in robot as well.
I will report back in a day or so with the results on all of this.