CMOS battery replacement

Benjamin Deering ben_deering at
Fri Dec 11 21:30:12 UTC 2015

The backup battery (supercap?) is welded to its bracket and
won't push out.

I replaced the backup batteries in my GTA02s with supercaps several
years ago.

The parts I used didn't match the original footprint so it was a little
work.  If you get the exact replacement part, it would be easy if you
have soldering experience.

I vaguely remember a software problem causing the line that charges the
backup bat/cap not being set high.

Good luck,


On Fri, 11 Dec 2015 12:26:54 -0800
Andrew Schenck <andrew at> wrote:

> The secondhand GTA04 I have now is pretty beat up and can't charge 
> because the USB port is disconnected.  I've been using a spare GTA02
> as a charger, but every time I switch out batteries the clock resets
> to 12/12/1999 16:00 and it's a pain to re-set it since network time
> doesn't work.  I couldn't find any information on the wiki about
> replacing the CMOS battery to solve this problem; has anyone here
> dealt with this same problem before and have recommendations?
> I disassembled a GTA02 enough to see the battery, but it didn't yield
> to gentle pressure trying to slide out of its bracket and I don't
> want to destroy things too badly in my attempt to fix them so I
> didn't push too hard.  Because of this, I don't even know the exact
> type of button cell to buy to replace it.  Any help would be
> appreciated.
> Thanks,
> -Andrew
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