MP 900 Loses Data After Main Battery Removal

Ok, I'm a relatively happy owner of a MobilePro 900 which I bought off of Isotherm through his thread: Link. But I've had one issue which is rather annoying (and troublesome). Even though I have a perfectly good backup battery in the MP900, I lose absolutely all my stored data on the device once I remove the main battery. (Think hard resets or changing batteries.) This has happened every single time the main battery is removed, I've even tried replacing the backup battery but it still happens.

About five minutes ago is the third or fourth time that this has happened to me. REALLY annoying seeing how I've got programs installed which I have to reinstall each and every single time. (Not to mention the data loss like contacts, office documents etc.)

Anyone know why this is happening? Or is it a faulty MP900 or just my ignorance?

Edited by SOLIDUS 2011-04-24 7:28 PM

i believe you when you say you have a good back up battery, but does it show up as good in your wince session? perhaps a bad contact?

That would be my guess...bad battery contacts, or cold solder joint on the circuit board. Doesn't happen when it is plugged in however and changing out the battery...does it?

Yes, the backup battery indicator reads "Good". I just took out the backup battery to have a look at the contacts themselves. They looked fine, but I bent them up just ever so slightly. I then made a couple of test documents on the desktop. After removing the main battery and inserting it, they're still there. Maybe this was the problem? Bad connection between the battery and contacts?

sounds like it, perhaps there was just enough play for you to lose your info when you pulled the battery and moved it around...

I was going to suggest giving the contacts and the coin cell a clean just in case there is any oxidisation.

One time I was in a pinch and didn't have a CR2032, so I used a CR2016 instead. I had to bend up the pins...but after a few months passed, I forgot about it and started having intermittent hard reset problems as well. It started driving me nuts until I realized that I had the wrong battery in place and the thing had gotten loose again.....

I have plenty of CR2032's, bought a couple of six packs from Radio Shack, so no 2016's here. (Although I have done the same on my Psion 5.) I'll out the battery again and see if I can't clean both ends just to make double sure.

Thanks guys, appreciate the help.

I left my MP at the office for about a week unused. The battery ran empty but it still had a full backup battery. I lost all my information, is this normal? As you can see from my above posts, I had an issue with the memory wiping itself after I removed the main battery which I had resolved. Could this be part of that problem?

Is there a way to make a copy of the entire WinCE set up to the memory card in case this happens? I'd hate to put the MP900 down for good, but I just can't have a computer that's unreliable.

Stick the backup battery on a multi-metre, it could be giving false positives.

I have like 20 new CR2032 batteries, so I'll try a couple of others and hope for the best. (No multimeter handy.) Thanks for the help.

Not a good sign....it should have depleted the backup as well....could be a bad circuit is not connecting the backup battery, or a bad contact....

Simple to test however, Just write a simple text file and save it to ram. Then pull the main battery and stick it back in....if the coin is working properly, then you should retain the text file. If it doesn't, then something is wrong with the MP hardware.

Also try the same trick with no coin, but keeping the a/c adapter plugged in and see what happens.

Hey Rich, thanks for the help.

See, the thing is is that in the beginning the MP900 would lose *all* data once I remove the main battery. I then fidgeted around with the coin cell battery contacts which seemed to have resolved the issue. I left it at the office due to Norwegian holidays and time off (circa a week) and I came back, everything on the MP900 was gone. I'm growing really sick and tired of having to keep reinstalling/moving apps around to customize my setup. But I tested it now again, it still retains the information if I remove the battery.

So to recap:
Originally it lost data upon removal of main battery.
I "fixed" it so it didn't.
Left it at the office, main battery went dead and it deleted everything.
Charged it, main battery removed and saved data stayed.

Truth be told, I'm about to throw the damn thing into a wall.

These things are meant to be plugged in all the time, whenver possible. If the main battery empties, which it will if not kept on a/c, then the backup battery will keep the data intact...but only for a short while. It is not meant to maintain the memory for days on end....only overnight, or about 12 hours.

The backup battery can still have the 3 volts it is suppsed to, but may not supply the current needed. The only way to really test a battery is while it is under load...not with a multimeter as voltage alone is not a true measure of a batteries potential.

That may be true Rich, I'm just used to having my Psion series 5 retaining all my old files even after sitting without batteries for a long time.