• From: Oslo, Norway
  • Registered: 2016-10-08
  • Posts: 24

Topic: Boot trouble "fixed" by unplugging battery

So I had trouble booting my Novena laptop with the same symptom as in the boot time problem: stream of systemd[1]: Time has been changed thread.

1) How do you know  if the power source below the DIMM is a supercap or a reachargeable battery? mine looks exactly like the one in the PVT2 top picture, green color an all, but there isn't any markings on the top side of it. Anyway, when the Novena is powered off it reads about 0.3 V. The DIMM covers it, so I can't measure the voltage when the machine is powered on.

2) I figured out that if I disconnect the main battery plug  (the large 4 pin Molex plug) the Novena boots fine, without any symptoms.

3) How is the battery charged? Through the main connector or through the smaller (balancing?) connector?

4) is it dangerous or wrong to plug in the main battery connector while the Novena is running?

5) Is it dangerous to run the Novena with the main battery connector disconnected?

Torfinn

2 Reply by chris4795 (edited by chris4795 2017-11-01 05:57:05)

  • Registered: 2015-05-31
  • Posts: 117

Re: Boot trouble "fixed" by unplugging battery

Hello Tingo,

I had the same problem you did:

1) I get 2.8V on that cap with no power now, and I had to replace it and it fixed that issue. I think I got 0.5V before I replaced it. It gives power to the Real Time clock, so when the board powers off, the RTC resets. On the Schematic it is "BR1225A". Check to see what time you get on boot up, it probably is reset every time.

This is the product on digikey:

https://www.digikey.com/product-detail/ … -ND/447501

3) the battery is charged through to smaller balancing connectors

4) I would not advise it personally, as that puts 18V at 1A directly on it. I would only plug it in when the board is powered off and AC power is disconnected

5) It is not at all dangerous. The battery board will just say there is not a battery.

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