Another PowerMac G4 problem

[Dave_S]

Hi all, Please be gentle!, new to these forums and Macs!, right, hope someone can shed some light on a G4 problem,... a friend of mine just bought me a PowerMac G4 to look at, unfortunately I don't know a thing about them...the problem is when I plug in the power cable to the Mac and other end (obviously!) to the wall outlet and turn on the power all I can hear immediately is a continuous clicking noise coming from the back of the Mac (power supply?), it clicks 5 times then a small pause and continues 5 clicks...pause etc..... power light comes on when i hold my finger on the power button but when i let go it goes off. No internal noises, no HDD or fan firing up, is the PSU shot?

Hope someone can help

regards

Dave

P.S I have removed the battery and re-installed as per another post on here to no avail....

 

[Dave_S]

BTW, I have just checked the voltage of the battery, 3.8v so that should be fine.....

 

[Spawn_Dooley]

Hi Dave_S,

It could be the PSU but if you replace that and the problem persists then it most likely will be a faulty logic board IMHO.

Have you tried resetting the PMU?

Does the power light glow or light up while you press the power button? If so, this points to a PMU error, which is relatively simple to fix, but also relatively easy to kill your computer in the process.

Power Mac G4 (AGP Graphics/Gigabit Ethernet): Resetting the PMU on the Logic Board

Power Mac G4: Computer Does Not Power On, No Fan Movement




 

[Dave_S]

It could be the PSU but if you replace that and the problem persists then it most likely will be a faulty logic board IMHO.

Have you tried resetting the PMU?



Power Mac G4 (AGP Graphics/Gigabit Ethernet): Resetting the PMU on the Logic Board

Power Mac G4: Computer Does Not Power On, No Fan Movement


Hi, Thanks for the info, I have just tried resetting the PMU (button very close to the battery), and tried to boot up again, still nothing. It still clicks 5 times as in my previous post.

When I hold my finger on the power button it lights up, but when I remove it it goes out slowly, like fades out. Just trying removing the battery for 10 minutes as stated on the Mac website in your links..........looks like its more serious than just resetting the PMU.............

Dave