Change iMac g4 battery

Carefully.

http://www.ifixit.com/Guide/Installing-iMac-G4-17-800-MHz-EMC-1936-PRAM-Battery/ 7039/1

This is a late post, but thought it might be helpful to someone.

Are any or all of these your symptoms?

-- dead iMac after disconnect from power outlet

-- replace battery but computer still dead

-- re-open computer, check cabling, etc., but still nothing

So, I thought my iMac was dead. But found others (with similar symptoms) on the 'net talking about letting computer sit (with power cord plugged in) for 24 hours (or more) and finally they were able to boot their computer.

Well, after my failure with the new battery, etc., I let my computer sit for approx 24 hrs (with new battery), power cord plugged in, and viola. After pressing the power on button, first some low level internal sounds, then a loud odd chime (not the standard), and within 15 - 20 seconds, that beautiful boot chime and computer back to normal.

I have yet to try unplugging power, so cannot report on that.

I'm actually an EE, but not in the electronics field, yet my gut tells me many of the mac computer products have some funky power management stuff. I'm guessing a long-dead battery does something weird that requires another weird kind of "charging", hence the fix with the 24 hour sit period. Just a relatively wild guess.

The reason for my post is to say, if you replace the battery, do not give up (I almost did). Try the 24+ sit with power plugged in.

If the computer is a late or last model iMac G4 USB2.0

they are mostly alike. Earlier 700/800/1.0 may not be.

•Mr Tote's iMac G4 take-apart:

http://www.mrtotes.co.uk/page1/page1.html

•iMac G4 Take-apart for Drive & RAM upgrade:

http://www.xlr8yourmac.com/systems/imac_g4/imacg4_takeapart.html

•How to identify iMac (Flat Panel G4) models

•A 3.6V PRAM 1/2AA Lithium battery, replacement:

http://eshop.macsales.com/item/NewerTech/BAA36VPRAM/

However a weak link is often a dead 3.6V lithium battery

and other than the massive tedium and cleaning of the

old thermal paste, applying new on reassembly, and a

skillful approach in working around a nightmare design

you may be fortunate to not have caused new damages.

While inside, if that's the only bad you find, is a fine time

to replace other components if you have new spares; &

check the internal factory RAM slot for an upgrade. The

iMac G4 USB2.0 can use a PC3200 chip instead of the

original PC2700 on the board. Be sure it is Mac spec;

even though it will be seen as PC2700. The other slot

near the AirPort Extreme card takes the SODIMM just

like the iBook G4 (mid-2005) uses as RAM upgrade.

With correct spec (or backward compatible in factory

slot) the RAM total can be 2048MB for USB2.0 iMac G4.

Good luck & happy computing! 🙂