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mrmagill
8-4-09, 10:04 PM
Hi folks -

For years, I have wished for a G4 for all of its video and graphics power. Last week, a friend GAVE me one! It was working fine when last used, but when I plugged it in this time it was D-E-A-D Dead. I am a skilled troubleshooter when it comes to PC's but I'm not sure where to start on this one. So, here's what I've done so far:

1 - Checked the outlet with a radio, power confirmed.
2 - Replaced the power cord with one known good, no change.
3 - Checked the 120/220 switch to make sure it was firmly in the 120 spot. It was.
4 - Wiggled the power cord at the power supply box to see if it might have bad contact.
5 - Opened case, checked for any sign of power (LED's etc) None found.
5 ½ - While the case was open, also watched for any sign that the fans were trying to run. None.
6 - Unplugged-replugged the ribbon from the start button in case it was poor.
7 - Checked most of the other ribbons for good connection between case and MB.
8 - Checked/confirmed memory firmly seated.

None of the above had any effect. Still DOA. Can anyone get me going in the right direction here, or suggest links that will help? I WANT THIS COMPUTER!!! :p but not as an oversized doorstop....

Old Macs used to have a key sequence you could use to stat them from the keyboard... would this one have it? Maybe the start button is just bad. The motherboard is BEAUTIFULLY laid out and easily serviceable in this machine... a thing of beauty.

Thanks in advance for any assistance -

Mark R. Magill
www.wordforlife.com

Edit: I just found a note that said, "The G4 processor..., was included on a wide range of its Macintosh computers..." This particular computer is a desktop version, not a powerbook or "portable" type.

KitBear
8-5-09, 04:48 AM
In reference to the G4:

It's worth testing or replacing the battery on the logic board. If the battery is dead or low voltage, that would prevent a power up.

Doc C
8-5-09, 10:22 AM
Or a blown power supply.

KitBear
8-5-09, 08:31 PM
Right, if the battery tests OK, then the PS is likely dead.

Doc C
8-6-09, 12:15 AM
Disconnect the power supply from the motherboard and that will take the battery out of the equation. (Although in all the years I've been working with PCs, I've never had one not power up because of a motherboard battery. But maybe it's different with Macs.)

KitBear
8-6-09, 02:52 AM
With that model, the battery is part of the power-up process.

mrmagill
8-7-09, 03:44 AM
In reference to the G4:

It's worth testing or replacing the battery on the logic board. If the battery is dead or low voltage, that would prevent a power up.

Thanks to each of you that replied, sure hope it's not the PS. Now at least I have a place to start. The system was working "perfectly" when last used and has been in storage for a while, so I hope it's a battery...

I'll work on it this coming week and see what I can find out.