I left it out for half a day already, no dice

Thanks for trying!

I had a similar scare over the weekend. The wall charger became hit or miss whether it would charge. Sometimes the wall charger would make the N900 think USB was detected. Connecting it to a computer would tell me it couldn't charge and USB mass storage would not work.

I ended up spraying some electronic switch cleaner (available from radio shack) into the USB port and that cleared it up.

Frank

Glad to hear it worked for you, but if Nokia finds traces of fluid it's not going to honor any claim for warranty and frankly can't be blamed. Used the stuff myself, but when it comes to expensive, in-warranty devices, it's best to let them take a whack at it first.

Hi,
I experienced similar problems (with original adapter) and have come to the conclusion that the charging software of the N900 is broken from design. Also, depletion can suddenly go very fast without any obvious reason.

So I bought a cheapo wallcharger and a second battery. When the battery in the phone is too far gone, I just switch them and charge the empty one.

I like the N900 for its commandline. But it will certainly be the last Nokia I will buy.

Paai

The battery management software has decade of legacy in it

The measuring relies on two crucial things: BSI (Battery size indicator), which is a resistor through the third pin on the battery, And the battery's true capacity.
If the two deviate too much, the battery state tracking gets thrown too far off, resulting in sudden big corrections.

The two (BSI and battery actual capacity) can disagree in some third party batteries, or if battery has aged significantly giving it lower capacity and higher internal resistance, or if there's poor conductivity between battery contacts on the battery and the battery terminals on the phone (dirt, corrosion, etc).

When charging, the software is very reluctant to admit/reveal if charge rate is lower than discharge rate. And, when it does, you probably miss the notification anyway. The response to input undervoltage conditions is to check whether voltage on input port still exists, and if so, retry charge at lower rate.
Thus, a power adapter unable to supply enough current, a damaged cable, excessive resistance at the connector (dirt, corrosion, too loose mechanically, etc) can cause charge rates below normal. A loose USB port can cause intermittent errors which can be misinterpreted as a weak charger. Multiple repeated intermittent connection issues in a short period of time can cause even stranger issues, such as the hardware chip resewtting itself to failsafe defaults, which results in a partial slow charge at best.
Again, connectivity issues between battery and phone can cause charging issues just as well as connectivity issues on input.

In the case of Solid orange light, there is no software running at all. The hw chip is doing an independent charge until there's enough power to boot. This should only happen if one disables bme and runs the device beyond the normal cutoff. If you reach such a situation, it's indicitative of a faulty battery or parasitic constant drain in the device itself. Also after prolonged periods at empty battery with the battery stored in N900 you'd see a few seconds of solid orange, that would be normal-ish. If it doesn't recover from Solid Orange to the next stage (which would see the solid orange replaced by glowing orange and/or reboots), it would in addition to the possibilities of parasitic drain and bad battery mentioned before also be a possible fault in the DC adapter, cables, port or N900. Further measurements and troubleshooting would be required.

If my device were in warranty, I guess I might have gave up my phone for days while they deny the claim due to some other reason. And I'm guessing if they haven't run out of replacement N900s, they soon will.

I didn't submerge the phone, just foamed up the connector slot, nothing into the phone itself.

thanks,
Frank

Small update.

I bought a spare battery, plugged it in and the phone booted up fine.
Both the USB cable and the wall charger are not detected when the phone is running and it doesn't charge.

When the phone is turned off and i plug the charger or the cable in, the led blinks orange couple of times, phone does a short vibration as when turning on, nokia logo shows up, then the dots.

After this it shuts down and starts doing the things i described before in a loop. I noticed that the battery is actually drained and not charged during this loop.

Thanks in advance, any ideas are welcome

Hello mate,

I had almost the same problem too. For me my N900 was fine but the battery pins were too wide to have a good connection. What you can try is ta make sure the battery is full. If you have a something like a baby pin try to push the connectors closer carefully and try it again on your phone. It might make a difference. Let me know if it worked.

I will give it a shot, although i tried with 3 different batteries already.

Another update. I have noticed that it gets unusually hot even when i don't run any apps that strain the cpu or even any apps at all.

I have the same problem. Could be that your usb connector is coming loose. Try gently wiggling it side to side and see if there is any play. The usb port on the n900 is shody by design and can easily come loose or even break off merely as a consequnce of what would be considered normal, every day use (I didn't abuse mine, yet it started coming loose a mere three months or so after i bought the phone). At this point, plugging in my (or a friend's) n900 charger goes completely undetected. strangely, the charger from a $40 Samsung phone works perfectly. Also, charging via usb cable worked well until recently.