For the last 3-4 weeks, my HCH II with ~33K miles has frequently lost it's entire charge from 7 bars to 1 or even zero. This happens when the vehicle is cool (not out in the sun or really hot inside), temps ~70-80 F outside. No heavy loads on the IMA battery. My dealer can't find a problem (need to wait for the "IMA" dash light) though they did install software updates for the IMA. These haven't helped noticeably. My ?? is, should I be waiting for the IMA battery to die? This has never happened this often in the last 2 1/2 years. I'm averaging 48-51 mpgs and I'm not riding the pack by any means.

 

There are a couple of active threads about this problem. Please post up on one of them and let this thread die out so we don't get a whole bunch of similar threads going on the same subject.

BTW, I'm having the same problem...

 

I would encourage anyone who is having apparent IMA battery issues with3+ years on the 12 volt battery under the hood to check it. Mine is dying, which is drawing more current from the IMA to keep it charged, thus draining the IMA battery and causing SoC issues. Just a suggestion, as $100 for a 12 volt is cheaper than an IMA repair.