On Feb 7, 2010, at 12:52 PM, Kevin Avery wrote: > OK, here is the status so far; > > All of the troubleshooting have done in the past on this iMac has been in the > dark, now in the daylight the "white screen" looks sort of grey. > > I was able to boot it into Open Firmware, I actually could see the words on > the iMac screen. So I issued the above statements one at a time, hitting > return after each one, no help, still a white/grey screen > > I have reset the PRAM using Option-Apple-P-R and let it bong 4 times, same > result. > > Hooking up an external monitor shows "input signal out of range", that is on > 2 different 15" flat panel LCD monitors, one is an NEC and the other is a > Compaq. I have no other monitors in the house to test with. > > I have been holding down the C key when trying to boot, i am pretty sure that > I dont need to at this point because I should be getting the folder icon that > comes up when it can't find a boot device. > > I have also removed and reseated the RAM. And I actually have removed the > third party RAM and left in just the 128mb of Apple branded RAM. Still the > same result. > > I removed the battery, it is definitely bad, it tested at 0.66 v DC, and is > supposed to be 3.6 v DC. I tried to boot it without the battery and have > gotten the same white/grey screen result. > > I appreciate all of your time and advice. > > What should I try next?
Here's what the Apple Service Manual says about a grey screen: Troubleshooting Symptom/Cure Tables: Startup Problems Before the Finder Gray Screen In a “Gray Screen Raster” situation, you will get a normal startup boot chime and the system will have a green LED. The display, however, will have a solid gray screen with no cursor or desktop displayed. Possible Cause Possible Fix Corrupted system software. - Boot off the system CD that came with the unit. Do you see a normal screen display now? Yes: Reinstall system software. (You must use the system software CD that came with the unit to get the correct version of Mac OS.) No: Go to next step. The PMU chip or logic board needs to be reset. - Press the PMU chip on the logic board with the AC power cord disconnected. (See “The PMU Chip” and “Resetting the PMU on the Logic Board” mentioned earlier in this chapter.) - Connect the power cord and power on the system again. Do you have power to the system now? Yes: Test the unit with MacTest Pro and return the computer to the customer. No: Plug in the AC power cord and reset the PMU chip again. Do you have power to the system now? Yes: The battery is likely bad, check the battery. No: Go to the next step. Bad video cable connection. - Verify that the CRT video board and video board cables going to and from the power/analog board are securely attached. If the problem persists go on to the next step. Bad SDRAM - Reseat/replace the SDRAM with known-good SDRAM. Bad logic board - Replace the logic board. Bad power/analog/video board - Replace the power/analog/video board. Bad CRT -Replace the CRT. The fact you're getting a chime/bong indicates the iMac is passing the basic system startup check, which is located in the ROM chip. You've replaced the battery, but may not have pressed the cuda (PMU reset button) to do the PMU reset. You may have a bad PAV board. OF video pretty much says the logic board, CRT and video cable connections are OK. Your two LCDs may not be capable of displaying the OF video output, which is pretty low res. I'll be they could display video if you could get the iMac to boot from either the optical drive or the hard drive. Try this, which has worked a couple of times for me when I ran into a similar startup problem: 1) Disconnect the optical drive and try to boot from just the hard drive alone. Don't press any keys. 2) If that doesn't work, reconnect the optical drive, put a boot disk into it, and try to boot the machine while holding down the Option key. If that gets a screen with a choice of boot drives, select one. 3) If that doesn't work, disconnect the hard drive and see if the machine will boot from the optical drive. I've had cases where something in either the optical drive or hard drive was kaflooey (tech term) and was preventing a boot. It took a lot of trial and error and, finally, "what the hell, might as well disconnect one" before I had success. If none of the above work, disconnect both hard drive and optical drive and try to boot from an external hard drive via firewire, or a boot disk in an external firewire optical disk. Connect your external monitor during this attempt. If none of the above work, buy another iMac and use yours for parts. Life is too short to keep beating yourself up over a 8-9 year old computer. Jim Scott -- You received this message because you are a member of the iMac Group, a group for those using Apple iMacs and eMacs. The list FAQ is at http://lowendmac.com/imac/list.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to [email protected] To leave this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/imaclist
