I am in the unfortunate situation that my N9 no longer seems to recognize wall chargers (no pulsing battery charging light in standby, no notifications or charging indications otherwise).

It probably discharged completely and at first I thought it was a hardware issue (micro USB socket failure).

If I unplug the USB cable from the wall charger and plug it into a notebook or desktop, the cable *does* get recognized (at least sometimes, this seems to have gotten worse than before) and charges (very slowly).

Any advice on whether this is likely a software or hardware issue? Would flashing possibly help? Anybody else having had the same issue?

Seems to be a hardware issue... Had the same issue on both my N9s and on both it was the freaking micro usb port that failed...

Hardware Issue, It happen to me!!! I just charge it with the Desktop PC, or car radio usb!!! but anymore with wall ones, and if try with those just moving the cable arounding the phone with it!!! ;P

Is this because different pins are used for USB-to-USB charging and USB-wallcharging? This is the only explanation I can think of, but then why does it work with USB car chargers?

No have idea that pins the same or not, by the way 'll check it information about it in the internet. but i know that mainboard microchips (condensators or something like this) are different which are controlling incoming chargs via usb-to-usb and usb-wallcharging. So, must check it with electronicer master whether is the usb-wallcharging controller working or not.

but the first, i think you must check software side, then check hardware. just backup your all data, then flash it (firmware&emmc all together), with zeroes flashing
zeroes flashing of firmware
then flash emmc
check this for mor information and guide to flashing options
by the way, if you will have cmt error during flashing, then find your old firmware, do the operations up there, then flash only cmt.

PS: DO NOT FORGET TO CHARG DEVICE FULLY. in your situation via noutbook\desktop.

check after this, whether does wallcharging works or not? and here are steps what you have to do.
1)detach all connections from Nokia N9 (usb,headphones ...)
2)if you dont have find the wallcharging controller,with which one you can switch off electric coming. if you have thats nice, so switch of electric from wall.
3)plug in your wallcharger to the wallcharging place (but not switch on yet)
4) plug in other side of your wallcharger to your N9
5)swtich on the wallcharging electric and see what happenning and let here to know.

Do these steps with your N9 when the device is working and when is powered off, try two variants.

PS: sorry for bad english

I have just dropped my phone, it slipped off the desk and dented the phone slightly around the headphone jack.

The phone soon died due to low battery. I used a 3rd party USB wall charger from a co-worker (from a Nexus 4 I think) and had big problems getting it to charge.

It started off charging then it said it could not charge (Like it does on a PC USB port sometimes). It eventually got going only to read around 300 minutes to complete.

It took 4.5 hours in the end normally 2h40min. I am hoping it was the charger but I cant see how it would be different to a Nokia one? unless it has a lower rating.

Could the drop have caused this?

Do you have USB transfer OK ?
Did you test other USB wall charger (mine died, and I'd to order new ones)

I am at the panicing stage. I'll have to wait until i have lost some charge and try with by Nokia charger which i know has alway worked.


will report back

Hopefully this explanation will be sufficiently technical to help, without being either overly-simplified or EE level . . .

There's a few modes that USB can be used for power (including charging). Your wall charger and car charger are probably both case 3 here, whereas connecting to a computer should start as case 1 and negotiate case 2.


1. low current. Initially, a device (like a phone) plugged into a host (a computer, etc.) will get a small amount of max current, 50mA IIRC so it can start negotiating with the host for more. Some devices may be able to charge slowly from this without negotiation, some may not.

2. negotiated current. After establishing communication, a device can request a higher maximum current by talking with the host, which the host can grant or refuse.

3. high current "dumb" charger. Newer wall warts, car chargers, etc. may use this. It's called BC1.1 DCP (Battery charging protocol version 1.1, dedicated charging port). This requires no data transfer between the charger and the device, the D pins are shorted through a small resistor. Some devices will follow this protocol precisely, and only pull high current from the wall wart if they detect the low-impedence between the D pins. If this isn't working on the device, it'll charge very slowly since the device will think it's not plugged into a DCP charger. This spec allows manufacture of low-cost chargers that don't need USB circuits and uC's inside.


(Oh, there's also a newer charging specification (BCP 1.2, I think) introduced circa 2012 by the USB industry association, but that's beyond our scope here.)

This ins't meant to be a textbook on USB charging or a replacement for reading the USB specs, which can be accessed at usb.org if one wants to build their own. I've simplified and left out quite a bit that I (personally) didn't think would help with the question.