Yesterday I noticed the MIL was lit. I called OnStar and the representative said my Volt showed codes P1E00 and P0CD2. She said that the lithium ion battery and the electrical system/HPCM are apparently not functioning correctly (to tell the truth, I didn't really follow everything she said). The Volt itself seems to run just fine, and it takes a charge (from my EV1 charger) just like normal. It's only the MIL that stays on -- no signs of a problem otherwise. Also no messages from the Volt on the dashboard readout. I've tried opening and closing the fuel cap and hatch a couple of times just in case but no change. Anyway, I made an appointment at the dealer on Monday. Any ideas? I hope, and would expect, that "lithium ion battery and electrical system/HPCM" issues are covered by my warranty.......