Looking for Pandora repair advice...

[NearTao]

I just picked up a used Pandora off of Ebay with a known "not able to charge" issue.  It turns out it is a CC device, and the case is held together with duct tape.  My guess is that somebody took it apart to do a repair and over tightened one of the screws.  Not confirmed, but the screw isn't holding the case tight.  So the starting bid price seemed fair enough for a mostly functional device... I certainly can't complain, and I do have a second Pandora that still works just fine, so I can certainly use it to charge additional batteries so all is not lost in the event that I cannot perform a repair.  

I imagine the case repair isn't two bad, and can probably be approached in several ways after a possible recharge repair.  I'm thinking super glue is probably a far more permanent and possibly not as great an option.  Seguru (spelling?) might be worth trying to fill the screw slot with a little bit and set the screw in.  I could use a bigger screw, though this could also make things worse.  Anyway, anybody who has attempted this kind of repair have any thoughts/suggestions?

The more troublesome issue is the recharge repair.  I have noticed a few somewhat alarming problems.  First, when plugged into a power source (I have a PSP wall charger among others) I get no indication of a recharge taking place, ie no power LED lighting up.  I checked and it isn't wiggly so I kind of doubt it's a bad connection here, but I haven't taken it apart yet to visual inspect it either.  Second, when I plug in USB, I get a charge light, but it doesn't appear to actually charge the battery, just that it slows down the battery power's discharge rate... but I may be imaging things, I will continue to test this.  Lastly, I've left the device off and it stills seems to discharge while the device is off, though again this may just be my perception, or signs of a bad/weak battery.

I have't really looked at the Pandora schematics, and I'm not certain what to check much beyond the solder joints on the power port terminal.  So if I get it apart maybe there are some circuits I should look at, or see if something looks like it got burnt out.  I'd be interested to hear some thoughts here, though if suggestions are mostly in the lines of leave well enough alone I'm sure I'll be fine.  On the other hand if there are a few things to inspect I certainly don't have any qualms checking them out either.

Thanks for stopping by and giving any help/insight that you may have.  It is much appreciated!

 

[comradekingu]

http://pandorawiki.org/Hardware_Hacking

http://pandorawiki.org/Power_modes

Feel free to make alterations or come with suggestions thereof.

Afaik there are pins to use with bench power source. Consult the hacker manual. There are PCB pics on the wiki too. Have a look to see if anything is out of place and if not, measure to see if it does what it should.

Charger and battery are possible external sources of error.

 

[NearTao]

Well I just popped the bottom off... and the right shoulder button isn't even soldered/glued completely to the PCB... I just touch it and it bends freely.  I'm thinking I have a few more things to check on my hands :/

Thanks for the links... definitely going to read up there now.  I probably new of them a few years back... but haven't had a need to do any hardware hacking... ever.  First time for everything though right!

 

[levi]

Are you running _wb_'s excellent System Info PND on it?  That can give you an indication where the power is going.  FWIW, USB charging will charge more slowly than barrel jack charging, but normally it's enough to overcome power drain and actually charge the battery.  My GHz Pandora uses under 1.1A with the screen on full brightness and wifi on, and I'd imagine a CC unit should give you something similar.

Regarding the stripped screw, first confirmed it's the hole that's been stripped, and not the wrong screw being used.  If the hole has been stripped you can rebore it and rethread it with the right tool, but you'll need a larger screw with the same size head, as tolerances there are quite tight.  An alternative is to glue the screw in the hole with a relatively soft glue like wood glue so that it should be possible to get it out again if you need to (and if you're very lucky, the glue will form usable threads for you and stay in the hole when you unscrew the screw back out).

 

[NearTao]

Oh I know that USB charging is slower than barrel charging... good reminder though.

Yeah I'm using the System Info tool to try and see what is going on here.

Plugging in the barrel doesn't register any change in voltage.  Oddly, plugging in the USB it detects the change and adds a (input: +<mw), but the Power value continues to remain negative while I watch the power drop.

With either the power barrel plugged in or the USB plugged in I can detect voltage on the battery terminals as well as the +/- terminals... which is odd, but perhaps there is a circuit in place that is faulty that would tell the battery to charge.  Unfortunately it's a little hard to triage for me at this point since putting the battery back in blocks the terminals making it rather tricky with the current tools I have to actually get a reading, and I don't necessarily feel like hacking something together... 

I did fix the case problem.  It appears that the previous owner swapped the long/short screws or busted the threading or something.  An additional longer screw seems to have resolved that issue.

One thing I did do was to pop up the battery terminals and cleaned them with some rubbing alcohol.  It seemed like they were making poor/inconsistent contact anyways, So hopefully that'll help something in some way.

So... after about two hours of poking with a multi-meter and taking it apart and putting it back together I think I'm fresh out of ideas.  If any suggestions do happen to pop up I'll be more than happy to try them... but at this time I think I'm happy enough that I fixed the right shoulder switch and the case screw issue.

Thanks guys!

 

[FBnil]

Does your power adapter have a PSP plug, with a small adapter to make it fit the CC? Mine actually requires lots of tweaking the connectors until its "just right", and even that is no guarantee that 10 minutes later the connection is not there (I bought a new charger, which just works).

 

[NearTao]

I do have the 'official' charger at work, so I will try there.  The odd thing is that when I plug it in and measure voltage/amp levels from within the case terminals it is definitely getting a connection.  I have a feeling that there is something faulty within the circuit, I'm just not sure where the problem lies or what needs to happen in order for it to tell the battery that it is okay to charge.

 

[levi]

It could be a battery contact problem.  If the battery's making enough contact to power the device but the sense pin isn't connecting, it can do weird things.  I'd suggest taking the battery cover off and holding the batter in with your fingers while you test the barrel jack to see if it performs any better with positive pressure.

 

[thatgui]

Plugging in the barrel doesn't register any change in voltage.  Oddly, plugging in the USB it detects the change and adds a (input: +<mw), but the Power value continues to remain negative while I watch the power drop.

Does the power value get positive on your second Pandora if you try to charge her (useing the same cable/power source) via usb ?

 

[Disposable1978]

What kind of options do I have for a repair?

The right shoulder button is the problem. There is no triggering mechanism on the board. ( purchased used ) The screws have been beat on ( partially my fault ) which inhibits easy acces to it's board.

In " what kind of " options " " what I specifically meant = could the fix be a service available?