G4 suddenly shuts down

Done that

Actually, I was asking the original poster too. Just seemed like we were getting into complicated explanations before looking into the simple stuff.

This may be nothing, but it may be something.
When My Nextel Phone rings, next to my G4, It shuts down. I didn't know why it was happening, I thought it was the heat, it wasn't. I blew the fans, changed batteries and so forth, I thought my computer was cursed, [ it probably still is though]. But I went back and thought about it, it didn't happen until brought me a Nextel phone, an I used it next to the computer. Then WHAM. Not every time, because I didn't notice it. But when I notice it went 2 to 3 days without shutting down, I notice my phone wasn't next to the computer. And as soon as I need to talk, and get next to the computer on my Nextel. I dialed a number, Then WHAM!, Things that make u say uhhhmmm? Any reason for this anybody?

Hi, Cordele!

My guess is BlueTooth, Airport, a wireless router, or even plain wiring is receiving a conflicting signal from the phone and passing it to the Mac. We had a weird audio beeping issue here about a year back, where a Mac's speaker beeped every few minutes. It was due to a cell phone which was receiving a periodic syncing signal from the phone company, resulting in the stray signal being picked up by the Mac's speaker. Best to keep the phone away from the Mac...

Gary

My G4 decided to shut itself down suddenly today whilst working in Logic Pro. When i tried to restart it got to the OSX bootup screen and then shut down again. After leaving it for about 5 minutes it would boot up but i would have a message saying that the clock had reset itself. This happened twice but now i've got it up and running again and running a disk repair program (just in case). It's not shutdown yet......

It's bloody hot in my studio (no A/C as yet) is this the problem.. or is there something fishy going on with my power supply/internal battery/... blah..blah..

Can anybody shine any light on this??

Rich

Steve and Paul,
My G4 has had the same spontaneous shut down problem, has been in the shop for 3 weeks now, has been tested for everything, supply is OK, front panel is OK, memory OK, etc., and now they say it must be the logic board. I am wondering if anyone in this thread with the similar problem was ever able to solve it and how??? Desperate here. Thanks!

Hi Paul,

I tracked down my unexpected shutdown problem to the Cinema Display. (I have had problems for a couple of years!) The logic board in the display had a bug which activated 'sleep' and 'power off' (and the reverse) as if I had pressed the on-screen button. This was a very troublesome bug, because I was not thinking outside the square. I always took the G5 itself to the Apple shop, who could never reproduce the problem.
Hope this helps.

Jim

After updating to 10.4.7, my G4 and Apple Cinema 17" would randomly go to sleep and spin down. I could wake up a few times and then "lights out". I would have to manually restart the tower by pushing the start button. I have since swapped out the monitor with a ViewSonic VA2012wb and the G4 has acted just fine. There must be a bug in the Tiger update and the Cinema Display.

IMac 500 MHz Mac OS X (10.3.9)