Suddenly my MacBookPro 15" doesn't think it has a battery. Energy monitor menu says, "No batteries available"!
I've tried everything that Apple recommends: restart, forced shutdown and PMU reset. No joy. The battery shows 3/5 lights; the computer runs fine on AC power, but dies if this is interrupted. This is my new replacement battery from Apple - see earlier post.
Google shows me that I'm not the only one with this problem (or similar).
Scotsys were helpful as usual. We tried swapping batteries with a demo machine. This showed that the battery had the problem (I suspect that this is a battery software problem).
In any case, I now have a battery on loan while mine is returned to Apple for replacement.
I also bought a spare power supply, as the connection between DC cable and magnetic plug on the original power supply is starting to fray.
New battery and new power brick have been working fine for a few months now. I still love my MBP!