[Nick_G]

I have an old 2002 vintage 800MHz G4 Power Mac that is going senile. Every time I put it to sleep, after a while it shuts down and has lost all the time & date settings when I power it up.

Is this a PRAM battery problem? I know it would cause the loss of date & time but would it cause my Mac to shut down as well?

Thanks in advance for any help.

[AKcrab]

There is a small 3.6v battery on the logic board. Replace it, they are cheap.

[reader50]

If you have a voltmeter, it's easy to check the battery after removing it. But loss of date / time does indicate the battery, and it's old enough. OWC is about the cheapest place to get a new one in the states, not sure about the UK.

If the battery alone doesn't restore normal sleep, I'd suspect the power supply next. It may not be supplying enough trickle juice during sleep - which would probably be caused by a dried-out capacitor in it. Also fixable if you are handy with tools & a soldering iron.

[Nick_G]

Thanks for the replies - it looks like a new battery is needed then.

[Nick_G]

Well a new battery was bought, the PMU was reset, and for the last week or so all has been fine.

Until this morning when I go to wake the Mac up - same problem as before, shut down & lost date/time info. So, a dodgy power supply then?

[reader50]

See if the new battery has been drained - check it with a voltmeter. If the PMU crashes, it can drain the battery in a couple days. Alternatively, if you got it in a local shop, it's possible that battery hung on the shelf for the last 5 years ...