DISCLAIMER: You do this at your own risk! There are very small parts on the circuit board and many of them are probably static sensitive. You WILL void your warrantee by doing this and I take NO responsibility for any of the procedures or information that I am providing below. This procedure fixed my phone, yours may be a different problem so you are on your own. Sorry I have to state all this, but you should understand that if you ruin your phone, it is not my fault. Also, if you have never soldered before – I would highly recommend you find someone to do this for you. Again these are very small parts, so you need a very fine tipped soldering iron with a low heat setting. No 100W soldering guns allowed ;-) I would also recommend you wear a static strap that is grounded and you work on a very clean hard surface. With all that stated – Good luck!
Tools needed:
Torx T5 dirver
Digital Multi-meter
Very fine tipped soldering iron settable to low heat
Acid free solder, very thin – NOT PLUMBING SOLDER
Solder wick
0603 size replacement fuse, 0 Ohm resistor, small piece of wire, blob of solder – something to repair the fuse. Obviously the best thing to do is to use a replacement fuse. The designer of the phone thought it was needed, but you do what you want. You can find suppliers of 0603 surface mount fuses on the web, such as
http://www.schurterinc.com . The fuse that was used is marked with an F, which signifies a 0.5A rating. If you want to go up a size or two, G is a 0.75A and H is a 1.0A. Surface mount fuses are notorious for de-rating after time, reflow soldering, etc. So very likely 0.5A is the correct size to use, but just after time or the manufacturing process the fuse just blew at a lower current level.
Take your phone apart according to the directions in the "How to strip your MPx200" sticky. You only need to remove the main PCB under the battery compartment. Once you have done this flip the PCB over and look towards the top and locate the fuse, see the attached picture. It is ironically marked with an "F".
With your multimeter check the continuity over this component, if it is open then your fuse is blown. If you have continuity over this part, then you have a different problem with your phone. I would start by checking the solder joints on the USB connector.
First, remove the old fuse. This is easier if you have two soldering irons. Then remove any excess solder from the pads with the solder wick. Then carefully solder the new fuse in it's place. There are other traces and components near by, so use as little solder as possible and be very carefull not to short anything else out. That is it, put the phone back together and see if it works.
This has worked on two phones, so 2 out of 2 isn't too bad. ;-)
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