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Could a dead PRAM battery be causing PMU problems?

Message #1 - Posted 2008/12/09 - Tom Anderson

Right,

No response to my last post, which was a bit epic, so here's a shorter one.

My Powerbook G4 will only boot after doing a power management reset. It won't wake from sleep either - i have to reset the PMU and then boot. If i do a PMU reset, booting is (so far) absolutely reliable.

Is it possible the PRAM battery is dead? Might replacing it cure the problem?

Thanks,
tom

I didn't think, "I'm going to change the world." No, I'm just going to build the best machines I can build that I would want to use in my own life. -- Woz

Message #2 - Posted 2008/12/09 - Jolly Roger

Previously, Tom Anderson wrote:

No response to my last post, which was a bit epic, so here's a shorter one.

My Powerbook G4 will only boot after doing a power management reset. It won't wake from sleep either - i have to reset the PMU and then boot. If i do a PMU reset, booting is (so far) absolutely reliable.

Is it possible the PRAM battery is dead?

The symptoms you describe absolutely may be caused by a dead or dying PRAM battery.

Might replacing it cure the problem?

Yep.

Send responses to the relevant news group rather than email to me. E-mail sent to this address may be devoured by my very hungry SPAM filter. Due to Google's refusal to prevent spammers from posting messages through their servers, I often ignore posts from Google Groups. Use a real news client if you want me to see your posts.

JR

Message #3 - Posted 2008/12/09 - Tom Anderson

On Tue, 9 Dec 2008, Jolly Roger wrote:

Previously, Tom Anderson wrote:

No response to my last post, which was a bit epic, so here's a shorter one.

My Powerbook G4 will only boot after doing a power management reset. It won't wake from sleep either - i have to reset the PMU and then boot. If i do a PMU reset, booting is (so far) absolutely reliable.

Is it possible the PRAM battery is dead?

The symptoms you describe absolutely may be caused by a dead or dying PRAM battery.

Might replacing it cure the problem?

Yep.

Thanks. I shall get onto it right away.

tom

X is for ... EXECUTION!

Message #4 - Posted 2008/12/09 - Tom Anderson

On Tue, 9 Dec 2008, Tom Anderson wrote:

On Tue, 9 Dec 2008, Jolly Roger wrote:

Previously, Tom Anderson wrote:

Is it possible the PRAM battery is dead?

The symptoms you describe absolutely may be caused by a dead or dying PRAM battery.

Thanks. I shall get onto it right away.

Er, does anyone know if the PRAM battery [1] from a third-generation 15" G4 will fit a second-generation one? I can get one of those on ebay much cheaper!

tom

[1] Which is apparently really called a backup battery, because it's powerful enough to keep a sleeping machine alive for a few minutes while the main battery is out.

If it ain't Alberta, it ain't beef.

Message #5 - Posted 2008/12/10 - Rob McCleave

Previously, Tom Anderson wrote:

On Tue, 9 Dec 2008, Tom Anderson wrote:

On Tue, 9 Dec 2008, Jolly Roger wrote:

Previously, Tom Anderson wrote:

Is it possible the PRAM battery is dead?

The symptoms you describe absolutely may be caused by a dead or dying PRAM battery.

Thanks. I shall get onto it right away.

Er, does anyone know if the PRAM battery [1] from a third-generation 15" G4 will fit a second-generation one? I can get one of those on ebay much cheaper!

tom

[1] Which is apparently really called a backup battery, because it's powerful enough to keep a sleeping machine alive for a few minutes while the main battery is out.

Check with www.ifixit.com They have downloadable instructions and specs for the PRAM batteries.

The PB G4 looks to be a right pain, with the battery a) expensive and b) glued down so you have to peel it off.

Message #6 - Posted 2008/12/10 - Tom Anderson

On Wed, 10 Dec 2008, Rob McCleave wrote:

Previously, Tom Anderson wrote:

On Tue, 9 Dec 2008, Tom Anderson wrote:

On Tue, 9 Dec 2008, Jolly Roger wrote:

Previously, Tom Anderson wrote:

Is it possible the PRAM battery is dead?

The symptoms you describe absolutely may be caused by a dead or dying PRAM battery.

Thanks. I shall get onto it right away.

Er, does anyone know if the PRAM battery [1] from a third-generation 15" G4 will fit a second-generation one? I can get one of those on ebay much cheaper!

Check with www.ifixit.com They have downloadable instructions and specs for the PRAM batteries.

They list the second-gen and third-gen PRAM batteries separately:

http://www.ifixit.com/PowerBook-Parts/G4-Aluminum-15-Inch-1-1-25-1-33-1-5-GHz-PRAM-Battery/IF154-017 http://www.ifixit.com/PowerBook-Parts/G4-Aluminum-15-Inch-1-5-1-67-GHz-PRAM-Battery/IF154-071

Which suggests they're different. They don't say enough about them to be absolutely certain, though.

The PB G4 looks to be a right pain, with the battery a) expensive and b) glued down so you have to peel it off.

I can get one off ebay for 15-20 quid, which is not so bad. New, they're a fortune, it's true. The main trouble with replacing it is the hassle of getting the case opened up, which is quite a bit of work - once i'm there, i'm not worried about a bit of glue!

tom

solvilvitur ambulando. copy a diamond shape, recording angel. .. ..

Message #7 - Posted 2008/12/18 - Florian Zschocke

Tom Anderson <twic@urchin.earth.li> schrieb:

Right,

No response to my last post, which was a bit epic, so here's a shorter one.

My Powerbook G4 will only boot after doing a power management reset. It won't wake from sleep either - i have to reset the PMU and then boot. If i do a PMU reset, booting is (so far) absolutely reliable.

Do you mean a Titanium or Aluminum?

Florian

Message #8 - Posted 2008/12/18 - Gregory Weston

Previously, Tom Anderson wrote:

Right,

No response to my last post, which was a bit epic, so here's a shorter one.

My Powerbook G4 will only boot after doing a power management reset. It won't wake from sleep either - i have to reset the PMU and then boot. If i do a PMU reset, booting is (so far) absolutely reliable.

Is it possible the PRAM battery is dead? Might replacing it cure the problem?

Never even saw the prior post. Didn't see *this* one until I saw someone's response to it.

The behavior you're describing is certainly consistent with a dead battery. I saw exactly that years ago in my mother's PowerMac 4400 (she burned through several batteries and it behaved like that every time) and I saw similar behavior this weekend from my own G5.

"Harry?" Ron's voice was a mere whisper. "Do you smell something ... burning?" - Harry Potter and the Odor of the Phoenix

Message #9 - Posted 2008/12/19 - Tom Anderson

On Thu, 18 Dec 2008, Gregory Weston wrote:

Previously, Tom Anderson wrote:

No response to my last post, which was a bit epic, so here's a shorter one.

My Powerbook G4 will only boot after doing a power management reset. It won't wake from sleep either - i have to reset the PMU and then boot. If i do a PMU reset, booting is (so far) absolutely reliable.

Is it possible the PRAM battery is dead? Might replacing it cure the problem?

Never even saw the prior post. Didn't see *this* one until I saw someone's response to it.

The behavior you're describing is certainly consistent with a dead battery. I saw exactly that years ago in my mother's PowerMac 4400 (she burned through several batteries and it behaved like that every time) and I saw similar behavior this weekend from my own G5.

Cool. I have a PRAM battery on my shopping list, although they seem to be rather rare on ebay, and amazingly expensive when new. For the time being, i'm PMU resetting before each boot, and doing without sleep.

It's a second-gen aluminium 15".

tom

It not infrequently happens that something about the earth, about the sky, about other elements of this world, about the motion and rotation or even the magnitude and distances of the stars, about definite eclipses of the sun and moon, about the passage of years and seasons, about the nature of animals, of fruits, of stones, and of other such things, may be known with the greatest certainty by reasoning or by experience. -- St Augustine

Message #10 - Posted 2008/12/19 - Gregory Weston

Previously, Tom Anderson wrote:

On Thu, 18 Dec 2008, Gregory Weston wrote:

Previously, Tom Anderson wrote:

No response to my last post, which was a bit epic, so here's a shorter one.

My Powerbook G4 will only boot after doing a power management reset. It won't wake from sleep either - i have to reset the PMU and then boot. If i do a PMU reset, booting is (so far) absolutely reliable.

Is it possible the PRAM battery is dead? Might replacing it cure the problem?

Never even saw the prior post. Didn't see *this* one until I saw someone's response to it.

The behavior you're describing is certainly consistent with a dead battery. I saw exactly that years ago in my mother's PowerMac 4400 (she burned through several batteries and it behaved like that every time) and I saw similar behavior this weekend from my own G5.

Cool. I have a PRAM battery on my shopping list, although they seem to be rather rare on ebay, and amazingly expensive when new.

This implies that you'd be willing to buy a battery used. I find that a strange notion unless you're planning on getting rid of the machine very soon and thus don't care how long it'll last.

They can be fairly expensive, but at least you're only replacing them every several years; many people don't keep a machine long enough to replace the PRAM battery. I do, as noted, but I can't imagine any business of more than a dozen people does today, for example.

Somehow the original battery on my SE from 1988 still seems to have a charge. Boggles the mind. I plugged it in recently after being in a case for over a year and the time was right.

"Harry?" Ron's voice was a mere whisper. "Do you smell something ... burning?" - Harry Potter and the Odor of the Phoenix

Message #11 - Posted 2008/12/19 - Tom Anderson

On Fri, 19 Dec 2008, Gregory Weston wrote:

Previously, Tom Anderson wrote:

On Thu, 18 Dec 2008, Gregory Weston wrote:

Previously, Tom Anderson wrote:

No response to my last post, which was a bit epic, so here's a shorter one.

My Powerbook G4 will only boot after doing a power management reset. It won't wake from sleep either - i have to reset the PMU and then boot. If i do a PMU reset, booting is (so far) absolutely reliable.

Is it possible the PRAM battery is dead? Might replacing it cure the problem?

Never even saw the prior post. Didn't see *this* one until I saw someone's response to it.

The behavior you're describing is certainly consistent with a dead battery. I saw exactly that years ago in my mother's PowerMac 4400 (she burned through several batteries and it behaved like that every time) and I saw similar behavior this weekend from my own G5.

Cool. I have a PRAM battery on my shopping list, although they seem to be rather rare on ebay, and amazingly expensive when new.

This implies that you'd be willing to buy a battery used. I find that a strange notion unless you're planning on getting rid of the machine very soon and thus don't care how long it'll last.

There is a good deal of sense in what you say. I do worry that buying a used one will be completely pointless, but the new ones are extortionately expensive.

I am hoping to replace the machine altogether in the spring.

They can be fairly expensive, but at least you're only replacing them every several years; many people don't keep a machine long enough to replace the PRAM battery. I do, as noted, but I can't imagine any business of more than a dozen people does today, for example.

True. It's annoying that the battery isn't some standard item, like a watch battery or something. It is on the desktops, right?

Somehow the original battery on my SE from 1988 still seems to have a charge. Boggles the mind. I plugged it in recently after being in a case for over a year and the time was right.

The time is always right for an SE/30!

tom

HE TORE HIS FACE OFF!!!

Message #12 - Posted 2008/12/19 - Gregory Weston

Previously, Tom Anderson wrote:

On Fri, 19 Dec 2008, Gregory Weston wrote:

Previously, Tom Anderson wrote:

On Thu, 18 Dec 2008, Gregory Weston wrote:

Previously, Tom Anderson wrote:

No response to my last post, which was a bit epic, so here's a shorter one.

My Powerbook G4 will only boot after doing a power management reset. It won't wake from sleep either - i have to reset the PMU and then boot. If i
do a PMU reset, booting is (so far) absolutely reliable.

Is it possible the PRAM battery is dead? Might replacing it cure the problem?

Never even saw the prior post. Didn't see *this* one until I saw someone's response to it.

The behavior you're describing is certainly consistent with a dead battery. I saw exactly that years ago in my mother's PowerMac 4400 (she burned through several batteries and it behaved like that every time) and I saw similar behavior this weekend from my own G5.

Cool. I have a PRAM battery on my shopping list, although they seem to be rather rare on ebay, and amazingly expensive when new.

This implies that you'd be willing to buy a battery used. I find that a strange notion unless you're planning on getting rid of the machine very soon and thus don't care how long it'll last.

There is a good deal of sense in what you say. I do worry that buying a used one will be completely pointless, but the new ones are extortionately expensive.

I am hoping to replace the machine altogether in the spring.

They can be fairly expensive, but at least you're only replacing them every several years; many people don't keep a machine long enough to replace the PRAM battery. I do, as noted, but I can't imagine any business of more than a dozen people does today, for example.

True. It's annoying that the battery isn't some standard item, like a watch battery or something. It is on the desktops, right?

Semi. And the degree of "semi" depends on the model. For a really long time, most desktop Macs used a cell known as a "1/2 AA" that you can typically find stocked in Radio Shack in small quantities. My mother's 4400 used some roughly cube-shaped thing with wires hanging off to connect to the board; always had to order those but they weren't Apple-specific. While looking up info to replace the cell in my G5 I found that the current ones are using a CR2032 which I can find in pretty much any grocery store nowadays. Can't remember what's in the SE, but I don't look forward to changing it when it finally does die because it was soldered in place on the early models. Was supposed to last for 7 years and I guess they didn't expect a significant number of people to need them replaced before they replaced the machine itself.

Notebooks are always a special case because of the effort to cram the necessary bits into the smallest space possible.

"Harry?" Ron's voice was a mere whisper. "Do you smell something ... burning?" - Harry Potter and the Odor of the Phoenix

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