nokia E72 charger

[jvdbossc]

Well I am not willing to repair it, plenty of cheap chargers around, but looking for some opinions about this.

About a year ago one of my (original) chargers went with a bang. Today some scratching noise untill the automatic switch off kicked in. another orginal charger wen't down, leaving me after 2 years out of warranty. (and a burned smell)

(original battery in there !)

The phone works perfectly, but it won't accept to load over an usb cable I am 99,9% sure that worked before!

I have two questions:

Can I cut of the wire of the psu and connect a labo psu to it with right voltage, current.? to see if the phone charges with that method.

I am planning to solve the problem permenant to buy a kit from hong kong with two batteries and an external charger and switch batteries...?

 

[mechtronics]

the original chargers that you had what output voltage were they? i presume that they were 5 volts givin that u r using usb. and my other question is is the battery in the phone wearing down fast??

is this kind of whats happening??

http://gsmangel-nokiahardware.blogspot.ie/2010/08/nokia-e72-not-charging-problem-repair.html

 

[jvdbossc]

Thanks for looking into this!

The charger is 5V (another port then the usb though) at 350 mah, it's very small.

The battery uuhm, not sure! If it is loaded it's good for a few day's then it's going down fast and a bit unpredictable. A morning alarm can cause that.

When you get the low batt beeps the cell phone can still last whole day without problems. It safes some extra energy and the battery seemed to recoup.

 

[mechtronics]

no prob, did u look at the link.

 

[jvdbossc]

yes of course, (its quite foolish and frustrating to ask for help and then not to look at all the options I get) but I cannot figure to be honest. I'll post a few pics. What I did found was that the usb connector had "white hairs" some sort of corrosion

 

[mechtronics]

ya id say there is a short somewhere in the phone possibly something is damaged

 

[duke37]

Seems as if you have had an attack of the dreaded tin whiskers. These have caused trouble in certain transistors and affected the space shuttle.

 

[mechtronics]

your spot on there duke something is shorting anyway!

 

[mechtronics]

you will just have to use a multimeter and go through the circuitry with a fine tooth come, maybe do some continuity and try and find out where the problem may be? might be tricky as components are small,

 

[jvdbossc]

If anybody could say wich is the fuse to messure? That would be the only thing left, exept changing the battery every time? Cleaning the usb did not help. I cleaned the connector with isoproph and bathed the connector in 90% ethanol several thimes...

http://imageshack.us/f/837/dscf0722y.jpg/

 

[mechtronics]

the orange looking thing on the top right hand corner i think. or else the little one on the right beside it. could be on the other side of the pcb too.

 

[mechtronics]

flip it over i think its on the other side.

 

[jvdbossc]

Thanks, I am looking, looking... the orange thing looks a cap it sais 6V. The other side:

http://imageshack.us/f/685/dscf0729v.jpg/

 

[mechtronics]

here u go.

 

[jvdbossc]

Ok thanks, I do not recognise much. But your pic is clear. The fusse is sadly ok. I found another link with usb pin outs they pass a fuse and diode ok as well..

 

[mechtronics]

the coil could be gone too try testing the continuity of the coil.

and test the capacitor.

 

[jvdbossc]

Ok the coil beeps out ok. How do I know the cap is good? I have no clue.

 

[mechtronics]

did you try both ends of the coil bottom and top?

 

[jvdbossc]

I just use both leads of the multimeter and hold it tot the bottom - top black smd componenent labeld as coil on the pic. It beeps then.. and say's 000

 

[mechtronics]

ok so, set your meter to ohms range and select a suitable setting ohm range on the meter and put your probes across each side of the capacitor, if the cap is ok ul see the resistance increase slightly ul have a reading at least.

if the cap is gone the reading will be 00.