U410 won't turn on unless it's plugged in


U410 won't turn on unless it's plugged in
My new Lenovo U410 arrived this morning, and I was excited to turn it on and set it up. After completing the initial set up with the battery at 90%, I turned it off and put it on to charge for approx 3/4 hours. When I returned, the battery light was fastly flashing amber, and this is doing so even now, when the computer is turned on and still plugged in to the mains. The battery is currently 99% and described as 'plugged in but not charging'. As soon as I remove the charger plug, the machine switches off. Equally when it is not plugged in the machine will not turn on at all. I'm not doing anything differently to this morning when I first turned it on and it worked perfectly.
The online manual mentions the battery pack being initially set to the sleep mode requiring the AC adapter in order to turn on the notebook for the first time. We got 2 U410's and 1 powered up without the AC adapter, the other required it. See pdf p17 of 44.
p27 of 44 shows what the status lights mean, a fast blinking amber battery light = battery has <5% charge remaining, slow blinking amber = charging has started but battery is <20% charged, slow blinking white = charging with battery between 20% and 80%.
When the battery reaches +80%, the white light switches from blinking to steady white BUT the notebook is NOT fully charged, it's still charging - there doesn't appear to be any indication when charging has reached 100%. This may be why some people are questioning their battery life - they may have thought it was fully charged when the white light switched from blinking to solid when really the battery is only ~80% charged.
I would suggest completely shutting down your notebook using the Windows shutdown option, unplug your AC adapter for ~10 seconds, then plug it back in and leave it charging for 4 hours and note what the battery status does. Hopefully it will go from slow blinking amber to slow blinking white to steady white.
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