Absolutely no! I must admit - it was late, when I've replied last time, and I missed this idea in his post. Unless You like smell of fried electronic at the morning, never do that.

You need to either connect ~4V power supply to battery pins on "fake battery", having BMI pin connected to ground via ~100kOhm resistor (if it's done this way, one may leave it - if not, tear connection apart, and re-wire everything), or do other trick, that I will describe on next paragraph. 4V power source may be hard to get (until someone like to connect 5V power supply through chain of diodes, until voltage drop to 4V - not so good idea), but this way, You don't need any other elements.

Easier, and IMO, more practical way of dealing with it, is connecting real, cheap BL-5J (any will do, even crappiest 400 mAh one) to battery pins in "fake battery", at the same time, breaking any other connection to battery pins.

5V power supply goes to pin that touch 5V testpad under battery, and ground, to ground.

This way, when you enter your docking station's fake battery into N900, You will have it working on battery (this real BL-5J, mentioned earlier), and charging, at the same time (thanks to 5V connected to test-pads). This way, capacity of BL-5J doesn't matter, as it is in fact running on charger power, with battery acting as big capacitor. If You do it smart way, You can every prepare easy-replace slot for that BL-5J, so you will be able to charge *any* BL-5J via N900 and your docking station.

All of the above, without USB port at all. Furthermore, if you mod "fake battery" to have pins for USB Data + and - in correct place, You will also have USB connection available (for flashing, or regular, every-day use, like mass storage mode, or hostmode, or whatever you feel fancy).

/Estel

This is very good idea indeed. I'm considering buying the JAF cable myself and modding it for the usb purpose. Will just need to source it in the UK first...

Estel, would you agree that the resistor should be connected to BSI pin rather than GND? The picture shows something opposite...

Resistor should be definitely connected between BMI pin and ground, not between battery - and ground (which indeed, seems to be the case on picture). That is, why I've suggested ripping whole thing on "fake battery" connectors apart, and putting cables connected to BL-5J there

/Estel

Just want to thank everyone on this thread for all the help in securing my USB. I am new to soldering with a hot iron, and with practice, I hope I did a good job (not cold soldered). To make sure I added a little bit of epoxy around the solder. The actual taking the N900 apart was easier then it sounds. Thanks again

Anyone here used Sugru before? If you have, and have soldered your USB port, do you think Sugru would help in any way? I have no experience with soldering and I am sure I'd just break my beloved N900 when trying to pre-fix it.

Hi dr_frost_dk, could it be possible to make a topic "fixing SIM port, before and after it is too late" like this one? I can no longer use my lovely n900 as a phone, and I think many people have exactly the same communication problems apparently because of another hardware fault...
(see there and there and there and there or there and the supposed fix method...)

Well this has not hit me yet, but if you have some time you can do it, most things i do here on maemo are not rocket science, i just like to keep things together to make the relevant info easier to find and more handy.
If i find the time ill look into it, but anyone can make a new combined thread.

Sure, as soon as someone find *real* fix for it, because current methods (paper between SIM and case, "hammering"), are rather uncertain and require good amount of luck.

Sadly, it seems that proper fix would require reflowing motherboard, which isn't thing that most people can do in home. I have theory, that method with disassembling to as bare motherboard as possible (including removal of keyboard matrix), then, putting it into oven pre-heated to 230 C degrees, for 8-10 minutes, could work. No joke - it's the way people use for repairing graphic cards, instead of paying 200$ for "real" reflow.

No one dared to try it with N900, yet.

/Estel

Does anyone in the UK have a spare USB connector that they don't mind parting with?

I have a second n900 that I would like to repair and the connector is twisted out of shape, I don't really want to buy a batch of them just for the one

I would be happy to reimburse you of course

One more quick q?

Is the internal plastic connection hard fixed to the system board and does the steel shroud slide away from it once de-soldered, or does it all come away in one piece?