Short Short Short Short Short Long Pause Short Short on a Portege Z30-C, means ?

Hi,

Does anyone know what the following white flash sequence on the 'AC Power light/Battery light' LED means, on a Portege Z30-C laptop ? Short Short Short Short Short Long Pause Short Short. I guess it's in the service manual, if anyone has. My Portege sometimes does it, when I press the power button to switch it on. The Portege then won't start, and instead just continually repeats this sequence.

The workaround I've found, from some clues on the web and experimenting, is to remove the power jack, remove the base, disconnect the battery, wait 2-3 hours, then hold down the power button for 1 minute, then connect the power jack, press the power button, see the message saying press F2 to set date/time in the BIOS, but don't because it 's fiddly, save and exit the BIOS, allow Windows to start, go to settings, choose set date/time, and press sync button to reset the date and time. Though sometimes, only a few mins with battery disconnected are needed.

Twice, the same has happened while the battery and power jack have been disconnected overnight, and I try plugging in the power jack, and pressing the power button. So perhaps the problem is not solely to do with the battery.

I bought the PC second-hand. It had a faulty battery initially, that powered off the PC when the level dropped to between 65 and 75%. Battteryinfoview reported that it was 75% healthy.

The selling company replaced the battery, under their hardware warranty. The replacement battery is also not completely new. Batteryinfoview reports it is 85% healthy. But it does at least discharge all the way down to 2%. That's as far as I checked. And the battery lasts a good 5 to 6 hours, which seems fine to me.
After the battery changeout, the laptop worked fine for a good week, before the LED flash sequence started happening.

Two days ago, I used the Windows option to reset Windows. And the LED flash sequence problem stopped. Though I wouldn't be surprised if it started happening again. Perhaps, after a week or two.
I would *love* to know what the LED sequence means . If some kind person knows, or has access to the service manual.

Googling for the sequence, or the service manual, has drawn a blank. I have the user's manual, but that unsurprisingly is silent on this matter.

Best regards,

David King