all of a sudden: no charging (usb or ac), battery draining insanely fast (est. 1h remaining at 70%)

[j0e]

hello everyone,

this morning I found that my Pandora was no longer charging. Usually when you plug in the AC adaptor when the unit is off, it turns itself on. This now only happens sometimes (it will always happen if i take out the battery and put it back in), but the red charging light doesn't turn on at any time when I plug it in when it's already turned on. I tried opening Pandora System Info to see whether anything was actually happening and noticed that the battery level was going down at an alarming rate: at 70% the program estimated that I had one hour remaining (when I usually have about 7 at that point) and the green bar was going down worryingly quickly. I tried using the charger on a PSP and it worked fine so it's not an issue with the charger. Remember that my pandora won't even turn on if a battery isn't installed and I plug it in.

Is my unit toast?

 

[TrashyMG]

If the Battery has been completely drained, it could take as long as an 15 minutes to an hour for it to slowly charge up enough to power on. Have you tried leaving it on the charger for a while despite it not powering on?

 

[j0e]

Hey, cheers for the quick reply. The battery hasn't been completely drained; it was at about 75% when the problem arose. I might leave it on the charger but another thing I forgot to mention is it got quite hot when I left it on the charger earlier, hot enough for the area between the analogue nubs to feel noticeably warm when I put my fingers on it. I've never felt that before on my pandora.

 

[TrashyMG]

It being very hot could be a bad sign... excessive current draw..  I'm not sure what it could be that is causing it, but it's most likely some kind of major issue with the hardware.

 

[mcobit]

Might be some short circuit. Can you open it and see if there is anything in there that could be causing it?


Maybe some loose component or a little metal thing?


Do the nubs and everything else work?

 

[dimag0g]

When System Info reported you only had 1 hour at 70%, have you noticed any unusual readings?

Specifically, the current higher than -500 mA could indicate short circuit inside your pandora, while low voltage (below 3.75 V) or low charge (below 1500 mAh) could indicate bad battery shape

 

[j0e]

Currently I'm at my parents' house for the weekend and I left my Pandora at home, but as I remember the system info reported a current of about -1700mA. I take it this is abnormal...

 

[TrashyMG]

Assuming the System Info is correct... Even if the CPU is pegged, it really shouldn't draw much more than 500mA  

I've done a bit of comparisons on the Pandora vs the OMAP5 if you check out the 2:00 minute mark I have the Pandora CPU pegged out running a h264 720p video.. 

 

https://www.youtube.com/embed/FOyjxOpL0WQ?feature=oembed

 

[moxie]

The battery has wriggled itself loose from the contacts. Open it up, take out the battery, clean the contacts if you like, Put it all back together again.

At least, that was what was the problem when my Pandora did exactly that

 

[Mr_Loon]

What happens when you try charging via USB?

 

[levi]

The area between the nubs getting warm is usually a sign that the CPU is working overload.  That might also be consistent with excessive power drain, though I've no idea how you'd get your CPU to consume that much juice without some hand-crafted code.  The power converter is located above the right nub I think, which I'd also suspect will get warm with such current draws.

FWIW, my power drain even with USB host on is still only 300-400mA.  That's around 15000mW in case that's confusing anything.  Check your battery capacity in System Info - if it's less than say, 80% of design then that would suggest to me the battery's not being detected properly, and quite normal current drains could give an estimate of 1 hour.  If on the other hand, the current draw is excessively high, and the battery capacity is normal, that would suggest that there's nothing wrong with the battery (or at least, you've got bigger concerns right now).  The current stats comes from the battery meter on the motherboard IIRC, so your problem is somewhere downstream of there - as mcobit suggests, a short circuit is possible.

 

[rohezal]

My pandora stopped charging via USB, then I bought a PSP charger and it started working again. Your charging doesn't work via the PSP charger, maybe you can try to charge it via USB?

 

[dimag0g]

Currently I'm at my parents' house for the weekend and I left my Pandora at home, but as I remember the system info reported a current of about -1700mA. I take it this is abnormal...

This is way too high, a usual sympthom of a short circuit inside a semiconductor chip. If you feel like investigating, I'd suggest to run your unit some time, and then open the case and try to find the faulty chip by touching them gently and and taking notes whenever it burns your finger  Nothing could dissipate 8.5 Watt of power during a couple of minutes without becoming noticeably hot.

If you have an amperemeter, it would be useful to make a real measurement to confirm the issue. Your unit should consume up to 600 mA without the battery and up to 1500 mA while charging at max. current. If you get a spike of current well above 600 mA when you flip the switch while on charger with no battery, I'd discuss with ED about repair options.

 

[moxie]

I know I said it before, but I'll repeat it: Before checking for shorts and all sorts of other stuff, do check the battery contacts. My pandora behaved almost exactly like that, including reporting silly numbers for current draw, when all that was wrong was a badly positioned battery.

 

[j0e]

The battery has wriggled itself loose from the contacts. Open it up, take out the battery, clean the contacts if you like, Put it all back together again.

At least, that was what was the problem when my Pandora did exactly that

Cheers Moxie, but the unit isn't even charging from the mains. If it was just a problem with a wobbly battery, the unit would still power up if I plugged it in without a battery, wouldn't it?

What happens when you try charging via USB?

Not a peep out of the unit for USB charging either...

 

[moxie]

The battery has wriggled itself loose from the contacts. Open it up, take out the battery, clean the contacts if you like, Put it all back together again.

At least, that was what was the problem when my Pandora did exactly that

Cheers Moxie, but the unit isn't even charging from the mains. If it was just a problem with a wobbly battery, the unit would still power up if I plugged it in without a battery, wouldn't it?

Nope. The problem I had, and I think several others have had at one time or another, isn't that the battery is not making contact at all - it is that it is making a bad contact. Wonky. Oxidisation or dust or something that makes the resistance to/from the battery greater than it ought to be. That would manifest itself as a longer charging time or even a charger that turns off prematurely (since it does not have the oomph to "push past" the extra resistance), and as weird data reported from "time left" and so on, since that depends on reading the voltage from the battery (if I'm not completely wrong), and an extra resistor (of some kind - dust, oxide, whatever) in the path will throw off the calibration of the measurements.

 

[j0e]

But if the battery isn't connected at all, the pandora should still turn on and work if it's plugged in to the mains through the charger port regardless of whether the battery's contact is wonky (since it isn't connected). My pandora doesn't do anything when it's plugged in. If you're suggesting that cleaning the battery contacts and making sure it's not wonky will make plugging it in work again when the battery isn't connected at all, I'm very skeptical.

If you feel like investigating, I'd suggest to run your unit some time, and then open the case and try to find the faulty chip by touching them gently and and taking notes whenever it burns your finger

hahaha, sounds like a good idea (it actually does!). I need to copy everything from my home directory on the nand to an SD card anyway so this will be an ample opportunity to find out which thing on the board is causing trouble. I'll report back later tonight with the results.

 

[moxie]

If I recall correctly, only a minority of the pandoras are able to run off the mains without a battery. Something with the construction of the charging/powersupply circuits. So I am not surprised at a pandora not running off the mains without the battery, no matter what the state of anything else

I'm not trying to say "I know exactly what the problem is" - I'm more going for "This is a possible problem with a very low risk/cost fix, so it makes sense trying that before doing things like opening it up or sending it away. It might not help, but if it does it'll save you a lot of time and effort". 

 

[dimag0g]

Maybe Nix could recall if his pandora was able to run without battery (on charger only) before the problems came? I know mine does.

 

[j0e]

I tried cleaning the contacts of the battery and the problem persisted I'm afraid. And yeah, I was indeed able to run my pandora off the mains without a battery in it before this all started, which is why I was concerned that I was unable to do this.

OK, so I ran it for a bit today to copy my home directory to my SD card. I also played a bit of Wipeout 2097 to get the unit nice and hot. The pandora still says only about 1 hour remaining, and I took some pictures and videos. I did try USB charging, and the red battery light flashes up for a tiny bit before going off again. System Info reports an input of power for the split-second the battery light turns on, then things are back to normal. Here's a screenshot of System Info:

I then decided to play some Wipeout 2097 and noticed that the sound is now sounding very odd. Anything above a certain threshold in volume makes the speakers crackle and fuzz, until the audio cuts out completely for a second. Video HERE.

After a while the unit got so hot I could just about smell the PCB if I put my nose close enough. When I tried plugging it into the mains, I only plugged the mains adaptor plug into the pandora for a couple of minutes but already the plug was very hot to the touch when I pulled it out. The area around the mains plug hole continued to be hot. After I turned it off I took the pandora apart but couldn't find any hot component in particular; the board was just generally very hot in the same areas shown below. Here's a diagram of how hot the case was after a few minutes of use with the unit:

Cheers for all your help so far. I'm pretty convinced that something on the board has gone wrong at this point.