Hi, this is my first post in this forum. I searched a lot but I couldn't find a solution to my problem.

The problem is this:

If I try to boot my N900 without a charger plugged in the following happens:

1. The phone immediately vibrates and a Nokia logo WITHOUT backlight appears.
2. After a couple of seconds the screen goes black.
3. The LED turns on in white, the slowly fades out.
4. The phone turns off and doesn't boot.

If I try to boot with a wall charger plugged in, the phone boots correctly.
The battery is fully charged, because if I boot with a wall charger attached, then I disconnect it after boot, the phone works normally for one day or two.
I also purchased a brand new battery, but I have the very same behaviour.

I noticed that also when I disconnect the battery, then I connect it again, I see the same behaviour described above (vibration, Nokia logo without backlight, white LED turns on and fade out). I can't remember if this is the normal behaviour when connecting a battery to the phone.

Another problem I have (maybe it is related) is that sometimes the N900 thinks to be still connected to the charger, also if it is not.
I see the yellow led blinking when the phone is locked, and I see the battery icon in the charge state when it is unlocked. Sometimes the phone leaves the false charge state after a while, sometimes the charge state lasts for hours, and the battery drains quite fast (maybe the phone doesn't use some power saving functions because it thinks to be connected to a charger)?

Thank you in advance for your help!