Hello all,
I have an Apple IIgs ROM01 motherboard that had worked fine 2 years ago. Now I have reconnected it, it does not work anymore.
When I start the IIgs (without plug-in cards and drives connected) then it shows the startup screen "Apple IIgs ....ROM Version 01" and then jumps into the monitor and shows a *. It does not accept any keystrokes, also you cannot get into the control panel. Only the self-test can be called up, the graphic changes 18 times, then nothing more happens (it stops shortly before the text intermediate message 04000000 with a functioning IIgs).If a drive is connected, it flashes briefly when turned on, the start screen is displayed and nothing else happens. Otherwise as just described.
I have tested the CPU, it is ok. Is the RAM possibly defective?
If someone has a hint I would be very grateful, I am otherwise at a loss.
Greetings
Wolfgang
Have you inspected the area around the battery for leakage, and mainboard damage?
FWIW, this might be a fried IWM data line or something equally tedious. I have two mystery-issue //gs mainboards and one WTF //gs mainboard (issues with only one peripheral, and for no valid reason). They are tricky to diagnose, and harder to repair as if it is an ASIC that is bad, it is basically a spare parts board.
IIgs__1.jpeg
IIgs__2.jpeg
Just for grins, try another PSU, push down all socketed ICs, and enure continuity on that bodge. if all of that fails, it;d end up in my basketcase bin. Could just be a recap issue. Hendy at ReActive will usually do diag and repair for US$100 to 200 on these issues. I frankly prefer to send the WTF //gs stuff to him as he knows more about it than I do. I know more about earlier modelds, than lattrer models, in general, and I have a widespread amount of knowledge that I freely share, but the //gs is a collection of ASICS.
This makes it a beast to diagnose, troubeshoot, and particularly repair.
I suspected it :-( I connected another power supply and also took out the socketed ICs and put them back. No success.
Nevertheless, thanks for the tips and help, now I have to go in search of a working IIgs motherboard. Does anyone have one for sale ?
If you are interested in selling this broken motherboard, I might take a chance on it. Let me know.
This sounds suspiciously like a failed RAM test, does it not?
I would socket and replace the RAM before I called it dead.