Macintosh IIci No display

[ExplorerZ]

Hello, I have a Macintosh IIci that wont display anything when powered on. Its motherboard has been recapped. When powered on it also does not play the startup sound. I have swapped ram and tried multiple new pram batteries. When I hold down the reset button the screen turns white. Could it be the power supply?

 

[imactheknife]

Hello, I have a Macintosh IIci that wont display anything when powered on. Its motherboard has been recapped. When powered on it also does not play the startup sound. I have swapped ram and tried multiple new pram batteries. When I hold down the reset button the screen turns white. Could it be the power supply?

Hello, I have a Macintosh IIci that wont display anything when powered on. Its motherboard has been recapped. When powered on it also does not play the startup sound. I have swapped ram and tried multiple new pram batteries. When I hold down the reset button the screen turns white. Could it be the power supply?

hi there, could be a lot of things. Broken traces, bad roms, bad solder joints. If it’s turning on i would think you would get a chime of some sort. Did board work before recap?

 

[joshc]

Got any high res photos of your board?

 

[ExplorerZ]

imactheknife, No it did not. Im going to try to get some photos. Quality might suck.

 

[ExplorerZ]

Got any high res photos of your board?

Not the best quality. Heres some photos.

 

[joshc]

The pics are too blurry to make anything out I'm afraid - but it's likely the Sony sound chips have cap goo on them, depending on how well the board was cleaned. Those chips are part of the reset circuit.

Have you tried with less RAM installed?

 

[ExplorerZ]

The pics are too blurry to make anything out I'm afraid - but it's likely the Sony sound chips have cap goo on them, depending on how well the board was cleaned. Those chips are part of the reset circuit.

Have you tried with less RAM installed?

Yes. And different types of ram. When holding down the reset button, the screen lights up. Color changed depending on the type or amount of ram sticks I use.

 

[imactheknife]

Yes. And different types of ram. When holding down the reset button, the screen lights up. Color changed depending on the type or amount of ram sticks I use.View attachment 52010

Bet it is a rom issue.. but could still be sound chips, reset issue

 

[imactheknife]

Bet it is a rom issue.. but could still be sound chips, reset issue

Are you confoortable with hot air station?

 

[volvo242gt]

If you can find a IIsi ROM SIMM, you can use that, too. Remove the jumper that enables the onboard ROM chips, install the IIsi ROM SIMM, then power it up. It should boot, then.

 

[ExplorerZ]

Are you confoortable with hot air station?

Don't have one. How should I go about this?

 

[ExplorerZ]

If you can find a IIsi ROM SIMM, you can use that, too. Remove the jumper that enables the onboard ROM chips, install the IIsi ROM SIMM, then power it up. It should boot, then.

I don't have a ROM SIMM or one inside the iici, is that why its not working? I'm a noob at this, sorry.
Edit: Nevermind, guessing the rom chips don't work and that's why.

 

[imactheknife]

Well, it can take a rom simm but you would have to remove jumper at w1 on the board. Where are you located?

 

[ExplorerZ]

Well, it can take a rom simm but you would have to remove jumper at w1 on the board. Where are you located?

Acworth, GA

 

[imactheknife]

Acworth, GA

Well, i have done enough to feel comfortable to look at it, but probably a lot of closer people to look at it too. A friend can make custom roms if needed. Will ask him if he is interested in looking at it. He is in florida, i am in Canada

 

[ExplorerZ]

Update: I messed up.. Kind of?
I toke off this from the part on the motherboard that said "Select Rom" or something like that. When trying to put it back on one of the metal pieces fell off. Now when i turn the machine on the screen is bright green without me pushing the reset button. Pushing the reset button does nothing. What do i do? Does this make it so I wont be able to use a rom simm?

 

[imactheknife]

Update: I messed up.. Kind of?
I toke off this from the part on the motherboard that said "Select Rom" or something like that. When trying to put it back on one of the metal pieces fell off. Now when i turn the machine on the screen is bright green without me pushing the reset button. Pushing the reset button does nothing. What do i do? Does this make it so I wont be able to use a rom simm?



View attachment 52080

The roms are soldered to the board. If you that you could use a rom simm in the empty slot instead. I think those are rare. So put that back on, or find a new one. Usually can find one on back of hard drives, or cdroms etc.

 

[volvo242gt]

1pcs PurpleROM new 2MB 64pin flash ROM SIMM for Apple Macintosh computers | eBay

1pcs PurpleROM newly made 2MB 64-pin flash ROMSIMM for Macintosh. The module is compatible with Macintosh computers with a 64-pin ROM SIMM socket and is similar to the BMOW Rominator & MacSIMM. Installing the ROM SIMM may require disabling on-board ROM by setting or removing a jumper on the...

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Scratch that. This might be a better option than what I originally posted.

 

[croissantking]

It could be the ROM but it could also be a lot of other things. Maybe a bad GLUE chip or a bad trace. A close visual inspection would be a good idea.

Could even be a bad oscillator, I know that I just get a green screen on my IIsi if the one that controls cpu speed is not present.

 

[Phipli]

Couple of things to check.

Do you have a soldering iron?

When you say you're removing different amounts of RAM, there are two banks (of 4 slots) that must be populated by the same type of stick within that bank. Bank A must be populated for the computer to work because the video uses that bank.

You probably don't need a new ROM and shouldn't buy one unless you work out explicitly that one is needed.

The fault is most likely in the power on, reset, sound part of the circuit. Start there. Look closely for mottled traces.

The jumper you broke is fairly easy to fix .

Be careful, those plastics are over 30 years old.