[wellard]

Hi, I would like go know if anyone has experienced similar issues as follows:-

After 2 weeks of owning my pb it stopped charging. The charge symbol would display for a few seconds and then change to a plug symbol and would not charge. It would slowly charge when connected to my PC so tech support suggested I have the charger replaced. Everthing worked great with the new charger for a few weeks.

A few days ago my pb shut down without warning with about 80% remaining charge. When it restarted it had dropped to about 30%. I plugged it in and it charged to 100% within a few minutes and then dropped to zero. I was running a great new app 'battery guru' which revealed the battery voltage was changing rapidly up and down. Also the % figure could go from 0 to 80 to 20 etc etc within a few minutes. It also showed that the battery health had dropped from 97% to 81% and the cycle count had stopped counting. In the end the pb would not power up unless plugged in to a mains supply. I reinstalled the os via DM twice as I thought the software may be corrupt, made no difference.

I called rim and got an rma and opted for an advanced replacement but told them to wait a week before dispatching as I was going on my hols friday morning (I called them Thursday).

Now the weird bit, Thursday evening my playbook started up on it's own and everything appeared normal. I ran battery guru again and the voltage and % readings were very stable. Friday morning the battery health went back up to 97% and the charge cycle went up 1 cycle. I've been using my pb as an e-reader and even typing this on it whilst tethered to my 9700 with a very weak gprs signal. Everthing is working as it should.

The thing is if I send my pb for repair they most likely won't find a fault and won't be able to replicate it. Also they didn't delay dispatch so the replacement is at the fedex depot. I am now wondering if it could be something such as static rather than a hardware fault.

So over to you guys; anyone else experienced this problem?

[peter9477]

The only explanation I can come up with for something like this, other than simple software defects (which is still a distinct possibility), is that you may have something like a "cold solder joint" on one or more legs of some of the chips in the system. That can lead to intermittent problems, sometimes but not always (and not even necessarily often) correlated to temperature.

There's generally one chip dedicated to monitoring current/power and involved in the battery charging circuit, and if it had, say, a poor connection on the pin that measured the voltage, that could lead to sudden changes in the reading. The effect of such problems isn't always just an "open" or "closed" connection either... it can just look like a higher resistance as well, which can affect the measurement without making it go right to 0.

Unfortunately, such problems are often extremely hard to troubleshoot. If RIM were aware of such issues, and respected their own measurements (which is all that Battery Guru is reporting), they might actually consider the export file proof of such a problem and adequate support for a return claim. If more was known about the internals of the device we might be able to reach that conclusion with certainty ourselves, but unfortunately we may never learn that level of detail.

[wellard]

Thanks for your reply Peter. When I finish my hols and back to a decent internet connection I'll email you my latest Battery Guru file. I've been running it none stop so all the freaky and currently stable data is there, just hoping it may be of some use to you.

I'll speak to RIM, not sure whether to send it away or not. If it gets worse over time at least your app can prove that there's a problem.

Just for the record I no longer shut it down, just using standby with the occasional reboot.

[peter9477]

I wonder whether shutting it down before was in any way involved in the problem. It's occurred to me that possibly charging with it off involves only some small and relatively dumb charging controller, and does not inform the higher level software that's involved in calculating that battery level estimate, the energy capacity, and all those other values.

From the start, other than maybe twice, I've always charged with the unit sleeping rather than off. I'll keep that possibility in mind as I watch the results people are getting with Battery Guru.

Thanks for the update @wellard.

[wellard]

Spoke too soon. Just as before wont work unless plugged in, no charge and battery voltsge goes from 3.4 to 4.2 volts within seconds. Replacement should be here Monday or Tuesday.