I stumbled on this thread through a google search looking for reasons why I was getting a "check bat" error on my brand new IPV D2. I was about to panic because so far I LOVE this device. Anyway, I found that in the process of screwing on all my tanks checking if I was getting the same error, I saw that the firing pin had become misaligned. I just pushed down on the spring loaded pin and readjusted it to the center and it cleared right up!