I can also vouch for shorting pins 2 & 3 (the middle 2)

I found a pin (the sharp kind, not the electronic component kind), and crossed one of the pins inside the USB connector onto the other. So now I can charge my N900 with my PowerMonkey charger! Not on the cable for the N900, but on female USB adapter I had... Didn't want to to ruin any cable that I actually needed.

i tested nokia's own dc-6, which is listed as compatible for the n900 but it doesn't seem to supply enough power if you want to use gps and listen to music in the car. if you do, the battery discharges slowly. the dc-6 puts out about 500mA.

i bought the following adapter for only 4$ and it works nicely with the n900. also, it puts out 1A which seems to be enough (your nokia wall charger has a current of 1.2A).much cheaper than nokias dc-10.

this is the charger i bought: http://www.dealextreme.com/details.dx/sku.26327 (that one was posted before in this thread). delivery might take 2 weeks or so.

cheers
pcerf

Ok maybe this is gonna help someone..
My Mobilize micro USB carcharger seemed not to work.

Then I turned off my Nokia N900, connected the charger again, and turned on my N900.
From that moment my Nokia N900 detected the charger and started charging..

In short connect you car charger and turn off and on your nokia N900.

I've tried a bunch of USB car chargers, and this one works fine for me in the USA. In the car, it provides 800mA. It also plugs into the wall for 500mA.

From Best Buy, sku 9812284

Pin2 and pin3 of the Micro USB cable need to be shorted together for most Nokia and Samsung phones to charge through Wall or Car chargers with USB slots ...

And take note that the chargers will be much more stable with 5V, 1A output for N900 since original charger comes at 5V, 890mA...

just my 2 cents ...

I bought this charger, plenty of power and no soldering required. Just got Lucky!

http://cgi.ebay.com/OEM-Motorola-Mic...item563a0ddd93

Search Terms: Motorola Micro USB charger

PIC:

To solve everyones problems! Buy a Converter at Best Buy so that your car can have a regular wall jack like your home. (roughly 50 bucks but it serves a double purpose) Now just plug in your wall charger in there or get a second wall charger and you are done.

This is good for two main reasons. One, you can charger your phone with no problems when doing long trips or when your phone is running low. Two, Usually when you buy a converter it has about 2 jacks on it making it useful not just for your phone but a laptop aswell or maybe a GPS or what have you.

I got myself one and love having my N900 and laptop connected at a park or long distance trip while i tether internet and make a speaker call! =)

-MASTER

following up, the cheap car-charger from DX works very well with N900.
http://www.dealextreme.com/details.dx/sku.26327
(However their 'Nokia' AC-10U wall-charger is fake and charges slowly.)

You mean a DC-AC inverter? Severe overkill, isn't it?
And for charging your laptop, a DC-DC converter is more efficient, so less likely to flatten the battery or blow your fuse.

I can confirm that this charger does work. My girlfriend had it for her former handset (LG VX-9100) so I didn't need to buy a new one.

However, I can also verify that this USB charger does not work with the n900:
Rocketfish RF-M357

i got this interesting prob....

am using nokia charger.
plug in the phone indicates charging.
after awhile unplug the phone few seconds the battery level dropped.
looks like it did not charge the battery?

is there someth wrong with charger?