Re: Soldering advice needed for re-attaching N900 USB to mainboard.
 

What I mean is, other threads have implied that soldering is totally easy and anyone could do it with no difficulty.This thread shows that not only are problems possible, permanently damaging the N900 is one possible outcome.

Re: Soldering advice needed for re-attaching N900 USB to mainboard.
 

dear frind i am showing u corect method how to repair usb

Attachment 26497
Make sure the flex between main PWB and SD-support PWB IS NOT BEND OR TWISTED SIDEWAYS.

after
Attachment 26498

Remove the old SD support adhesive tape from the shield carefully with the same plastic stick

Attachment 26499

Remove old SD support adhesive tape from the SD-memory card PWB package

Attachment 26500

Make sure the flex to SD-support PWB IS NOT BEND OR TWISTED SIDEWAYS.

Attachment 26501

Clean the adhesive areas.

Re: Soldering advice needed for re-attaching N900 USB to mainboard.
 

WTF is that, some kind of auto, semi-intelligent spam?

Re: Soldering advice needed for re-attaching N900 USB to mainboard.
 

Great information guys!!
I just repaired my constantly failing USB connector. Near to trash all the phone. Tired about this sh**.
Really, we can be honest, it is not the best phone of the world. I do a mistake buying it. But now I have it and if I have it I want to use it.

I'm technician and know how to do that kind of works but I don't have all the knowledge and information. Just your pictures about the 5V location and your demonstration of what know and using my brain was the power I just got it!

Trying to repair it I damaged the copper in the 5V pin. So I missed that. Now I just take a piece of a copper wire from a electrical wire and with that little thing I jumped from the connector to the 5 Volts (above the SMD component). Thank you very much guys!

Just to take in account I want to suggest to new people trying to do it:

1- Make your space for work. Put the PCB of the phone in a table or piece of wood. A little (sized to at least two PCBs) piece of MDF is enough.
Take off the micro SD card reader. Just as you can see in the pictures in this post (messages above). Press and sustain it with something so you can work without you bothering.

2- Reinforce the connector itself. You will need a powerful solder iron (100 Watts). With a sandpaper scrapes off the varnish near the metal of the connector (just to give it more space in each side where you can). Don't try to scrap in difficult places. Do it softly and with attention trying to don't damage near components.

Then begin to solder with a 100 watts solder iron. Ensure to heat well but not too much (you can damage near components if you do it during a long time = 20 seconds. In that case stop and wait until it cold, then retry). Heat the connector and apply solder wire, enough to cover all the side of the connector but not to cover the connector itself (you can ruin it).
You must sustain the connector with a gripper or something appropriate for that. You must sustain it before you heat it and after it becomes cold.
If you don't sustain it, it may be loose and welding will be of poor quality.
So, to ensure you soldered it well you must sustain it firmly from where you see the solder smelted like liquid and after you feel it near cold (and solid).
That will be a good welding.

3- Make more space for work with the pins now. Take out the metal plate (a lid) that covers the chip. With some screwdriver and a gripper you can help.
With a pliers or something like that you must cut the metal that cover your space to work with the connector (not the lid, you must cut the metal soldered to PCB that crimped with the lid).
Cut only that piece so you can put later the lid newly. Try to don't damage nothing, be careful doing that.
Now you must straighten a little piece of metal from the connector (the piece that covers the back of the connector). While you try to straight it, it will cut off. No problem, just leave it so, we don't need any more that fu**** piece of metal. That just cover us from seeing the pins.

Follow the instructions of the old messages in this post for understand it better.

I just wrote this to take in account not for the only and final elite solution. Take in account my suggestions but search for more information too.

4- For reworking / soldering the pins use a small soldering iron. Don't use the 100 Watts one!! Use a + - 40 watts soldering iron. I used a regulated temperature soldering iron with a very tiny tip so I can put it in the very little pins and very near spaces without touching anything except the pins.
A guy modified a standard soldering iron tip just adding a copper wire coiled around it. That was a good idea!

If you can get something like that (a tiny tip), you don't need to disassemble the camera. I prefer to disassemble the less things what I can. Each thing what you disassemble can becomes damaged or malfunction. And gives you more work.


5- Take in account that if you melt a lot of solder wire over the pins here are the solution!!:
Don't try to force nothing, that will be worst.
Use some resin. Just put your solder iron in the resin and rapidly heat the melted pins. Magically they will separate!

I was near to losing all because that (melted pins). And just give a opportunity to resin. Luckily that was the solution!

As a security measure always use resin for finish your work. Next that you can be secure about nothing is touching that don't must and all that must be soldered will be.

6- Protect the flex of the screen.
I used a soft napkin paper (from kitchen or bath room :P) or you can use cotton too. Take a spray of "four in one" oil and moisten the paper/cotton a little. Now pass it over the metal where the ribbon slides. Try to moisten the metal. Repeat If you need more oil.
Use the oil to clean some metal pieces too (external not internal, don't use oil for internal components/pieces!!). Don't put it in excess, it must be superficial but in the place where the flex slides you can put a little more.

The flex can wear from use. If you use oil it can have more lifetime.

7- With that kind of oil you can clean too the lens. Because it is a very refined oil (WD40). If you use a thicker oil you cannot use it for cleaning lens. Only WD40 worked for me. And the results are amazing. You can clean the viewer of the camera. You can clean the screen and so on.
Of course, use it for moisture, next with a hyssop (that you use for cleaning your ear) you can clean the lenses and pass it very times as you need / see the lens clean. With the hyssop or a cotton you will quit the excess of oil. Do it after you don't observe presence of oil (you will feel more friction in the cotton). And in meantime you can see how it becomes clean and more clean (I managed to leave it so clean that it seemed there was nothing, even a glass).

Of course there were some hairs/rests of cotton so I used a very little gripper (for electronics) to take that. You can use a clip of wax small.


8- If you have problems in the USB. There some things to consider:

You can have shortcircuited the both pins of data (the middle ones). The symptoms are: The phone can be charged with the wall charger and with computer but cannot detect the computer and the computer don't detect it. That is because Nokia use the two pins of data short for a charger.

Your phone charges and is detected a lot of times in the computer but never work as USB storage. I just received it in syslog:
usb 5-2: new full speed USB device number 47 using ohci_hcd
usb 5-2: new full speed USB device number 48 using ohci_hcd
usb 5-2: new full speed USB device number 49 using ohci_hcd
usb 5-2: new full speed USB device number 50 using ohci_hcd
usb 5-2: new full speed USB device number 51 using ohci_hcd
usb 5-2: new full speed USB device number 52 using ohci_hcd
That is because you have one data pin shortcircuited to ground.


Your phone don't charge and when you move the connector it charges but not last too much. It is because you have the pins desoldering. You must proceed to repair your connector.


Some problems related to USB disconnections or slowdowns maybe the phone connector but too the PC connector (not soldering problems but poor quality specially the front ones).


I think the connector of this phone is the worst in the world.
I have repaired it now but anyway it is not perfect and sometimes it fails, specially with:
usb 2-5: reset high speed USB device number 2 using ehci_hcd

It never worked correctly, always had some errors.


Well. That is all, folks :P

Re: Soldering advice needed for re-attaching N900 USB to mainboard.
 

That is because if you don't need to solder the pins you need only to reinforce the connector. And that is not too difficult to do. But you must do that soon if your connector get out of place. If not you will need to solder the pins too. And that is the hard/dangerous part.

Re: Soldering advice needed for re-attaching N900 USB to mainboard.
 

Honestly? It is. At least, if You want to have mobile computer with mobile phone function :)

Re: Soldering advice needed for re-attaching N900 USB to mainboard.
 

Could you please tell use which phone/tablet would do better than this one?

Re: Soldering advice needed for re-attaching N900 USB to mainboard.
 

NO!

Absolutely no for changing this thread into another "mine is better than yours". We already know the usual arguments of Android kids and iSheeps, no need to rewrite them here again.

/Estel

Re: Soldering advice needed for re-attaching N900 USB to mainboard.
 

OK sorry man.

BTW

Thanks for the debian chroot image

:D

Re: Soldering advice needed for re-attaching N900 USB to mainboard.
 

Yes, it's a bit late for that. I gave up and already bought a used N900 with a working port and transplanted all the SD and eMMC contents to it so it's identical to my old phone in every way.
But I will take your advice into consideration if I ever get the courage to get soldering the old phone again.

Good tutorial, mate! If only you'd have pics with that one, it would be worth putting on instructables.com (no endorsing here, carry on) :D

Re: Soldering advice needed for re-attaching N900 USB to mainboard.
 

thanks lazart. i flashed my device without usb port by this way.
thanks for information.

Re: Soldering advice needed for re-attaching N900 USB to mainboard.
 

Please could somebody advise the which post has the definative instructions on how to reflash without using the usb port but by using the pads on the motherboard.

many thanks

Nig451964

Nokia N900 Problems
 

Hi All,

It looks like N900 has given us more problems than easy usage of the mobile as a normal mobile. I am also a victim of the Nokia Care irresponsibility about Nokia product.

It looks like the Nokia Care guys cannot repair their product with confidence, but the customers do!!! Strange, isn’t it? That’s something shocking because Nokia technicians should be considering the option of going back to the school days and learn how to repair the product and come back or fire them and get the talents in.

My mobile was not booting up due to the fact that the power kernel was uninstalled by mistake. I explained the case with the Nokia care guys and I told them I am unable to flash it because I am using Windows 7 Home Premium 64 bit OS in my laptop and it is not recognizing the USB device for flashing. I know that we can flash it with Windows XP without any difficulty, which I did earlier. Also it is possible with same OS in XP compatibility mode. I didn’t want to install an XP or moving it to compatibility mode for just flashing my N900; rather I prefer paying some amount and getting it done from Nokia Care. To my surprise the technician told me that it is very difficult to flash and there is no guarantee that the device will work properly after flashing it. He gave me a 50-50 chance.:eek: I told him that I did flash my device earlier and I can give you 100% guarantee that the device will work absolutely fine after flashing it.

I took my mobile back and flashed it in my friend’s system with XP OS and it was working 100% fine.
I feel sorry for this Nokia Care guys. They do nothing but show off as if they are up with ‘it’s not our responsibility to repair YOUR device, if you want me to repair pay me half of the actual device cost.’

Regards,
Jiju Joseph.

Re: Nokia N900 Problems
 

This is someone that clearly doesn't understand the N900.
There unlikely to mess with an obsolete product usless they have to.

I'd of tried this first.
This has nothing to do with this topic BTW.
If you read the reflashing wiki you will find Window 7 can have compatiblity issue especially if 64 bit.
Your USB doesn't sound broken.

Re: Nokia N900 Problems
 

Hi Sixwheeledbeast, I was actually following the posts of "PipBoyBSOD" and I felt sharing my experience with the Nokia Care.

Yes, as you said the person was not much exposed to N900, which I also felt from the reply I received from him.

For the second point, yes, I have gone through the wiki and I am aware that we have work around for windows 7 64 bit, which I didn't want to do because it is so easy to flash in XP and hardly takes 2-3 min time. My USB isn't broken.

Regards,
Jiju Joseph.

Re: Soldering advice needed for re-attaching N900 USB to mainboard.
 

Hi,

My N900 was in charging and unfortunatly he fell down and the usb connecter became totaly loose.

So I opened the phone and I took some pictures.

Can you tell me if you think this is repairable or you think I have to replace the mainboard ?

https://lh6.googleusercontent.com/-R...0/DSCN0743.JPG
https://lh6.googleusercontent.com/-y...0/DSCN0747.JPG
https://lh6.googleusercontent.com/-c...0/DSCN0748.JPG

thank you
Thib.

Re: Soldering advice needed for re-attaching N900 USB to mainboard.
 

Hi. About half year ago I faced with a similar accident.
Let me to explain my opinion. According to Your photo, the contact fields on the motherboard remain undamaged, except massive ground one.
I think You can reuse the old detached connector for your soldering work.
I had used an soldering iron with some sharpened copper wire coiled around (wire thickness around 1mm ). To solder the thin contacts You must be very accurate and use some magnification glass and liquid flux.
Useful links:
How to reattach the ground.
http://talk.maemo.org/showthread.php?t=75920
Good luck!

Re: Soldering advice needed for re-attaching N900 USB to mainboard.
 

I would use new USB port, with little longer pins - it's easier to solder than old one, so less risk of destroying pads during first attempt.

/Estel

Re: Soldering advice needed for re-attaching N900 USB to mainboard.
 

My N900 was damaged during a car accident, I am claiming for funds to buy a replacement N900.

Anyway, the microusb fell out! The micro usb tiny pins stuck to the board so I have to order a new one. All the solder pads are intact so a repair should possible.

I have no way to charge the batteries at first but I do own an NXT-R3 UHF radio! I was able to charge my BL-5J batteries overnight to full capacity by connecting the usual +- to the appropriate terminals of this radio.

Re: Soldering advice needed for re-attaching N900 USB to mainboard.
 

You just have to be able to solder SMD. A tiny soldering tip and desoldering wire.

search for "BL-5J wall charger", I used mine long for charging this way. And still sometimes, because I got 3 batteries. Better than always clip some wires on (I used a regulated power supply and soldered wires behind the enclosure of the phone for a while^^)

A tip for changing batteries: if you change them fast enough (few seconds) when the phone is turned off, you're system time won't be lost :)

Re: Soldering advice needed for re-attaching N900 USB to mainboard.
 

Thanks for that tip I will have to try. A wall charger is on the way and I picked up a selection of extended capacity batteries. One of the brands I have not tried before is a Bilitong 3LT Gold, looks legit.

Is there another way with soldering paste, maybe a hot air rework station?

Re: Soldering advice needed for re-attaching N900 USB to mainboard.
 

n900s usb is to be solderd on the board though you can use hot air station to reinforce it :) hot air gun can be used to fix a bit diffrent type of same connectors where soldering desoldering is not an option but they are to be fixed with a hot air gun :)