mac turns on for about 15 seconds, wheel spins and shuts off help

[econtrerasguzman]

since yesterday my imac G5 started having problems booting into the hard drive, it randomly shuts off about 20 seconds after the chimes. any suggestions? could it be a failing hard drive? i took out the memory and it boots, tried placing one stick at a time but it doest the same, chimes then shuts off any suggestions?

[Case]

Can you boot from the System DVD? (Hold 'C' (for Compact Disc) when you hear the chime, to force the machine to look for a bootable optical disc to start up from.)
If it does, do not go into the installer, but select Disk Utility from the menu, and try to 'repair' the hard drive.
If you get the hard drive to work again, install SMARTReporter, to keep a close eye on the disk's S.M.A.R.T. status.

[econtrerasguzman]

is that the CD that the Mac came with? (sry its a class computer and im not familiar with the included CD's)

thanks

[tomlee59]

Case is referring to the OS installation CDs or DVDs that came with the computer. You can boot off of them and use the disk repair utility (also on the disc) to try to fix things. If it can't fix it, you'll need more heavy-duty third-party disk tools (or possibly a new disk).

But if this is not your computer, then this task should be performed by whoever it is that has responsibility for maintaining it. School computers shouldn't be modified by students without permission.

[econtrerasguzman]

I AM RESPONSIBLE FOR MAINTAINING IT AND I HAVE BEEN GIVEN PERMISSION, I DONT MEAN TO BE RUDE BUT YOUR RESPONSE HAS NOTHING TO DO WITH THIS FORUMS TOPIC, THAT IS SOMETHING THAT DOES NOT CONCERN YOU. THANK YOU

[econtrerasguzman]

holding C didnt work, we were able to hold n and get it to come up with the network boot, but we have nothing on the network to boot from. any more suggetions?

[Case]

Booting from an OS Install DVD or CD has worked for me in the past, when encountering faulty hard drives.
Make sure you get the right Install DVD, or the machine won't boot from it: The iMac G5 (2004) requires Mac OS X 10.3 or later; the iMac G5 (May 2005) (ambient light sensor) requires Mac OS X 10.4 or later; the iMac G5 (October 2005) (integrated iSight webcam) requires Mac OS X 10.4.2 or later.
If you can, open the case to see if everything's still connected inside. (Opening may not be as easy as with a tower casing.) I've seen some abused classroom computers, which makes it worth checking...

Also, some of the first generation iMac G5s have been known to have power failures, for which there is a repair extension program. See Apple's page on this issue for details.

To identify a G5 iMac, as there are 8 models of them, check Apple's How to identify your iMac page.

[terryj]

Do not forget:
The computer could be locked in Open Firmware,
thus preventing it from booting from an OS Disc
altogether.

I've routinely done this in the past to client's machines
(especially laptops) to prevent them from being
booted up from an OS Disc if ever lost or stolen.
This is often done at the request of Corporate Administration;
School Administrator's might be different, only your
Technical or Cirriculum Co-Ordinator would know
for sure, as IIRC, they are the ones responisble for
the Initial setup of the machines, while the local
site techs just do the day to day routine stuff?

Another thing to try, if you haven't already, is did you
try a FW Target Disc mode on the computer?
It is fairly easy to do; just hook up a FW cable to
the problem mac, the other end to a good working mac,
boot up both, but hold down the "T" key on the keyboard
attached to the problem mac.

Unless the HD is totally shot, the boot sequence will be bypassed
on the bad mac, and the HD will mount as a slave (external)
to the good working mac. From there, you can run Disc Utility
on the Good mac, and see if it will repair it ( the bad mac's HD).