I’ve got this iisi that displays a yellow screen on boot up with no chime or anything else. I’ve recapped the power supply and the logic board. I’ve removed all the ram and this is the board with the rom on the board. I’m not sure where to go from here. Any ideas?
How heavy was the cap leakage (and battery leakage) on the logic board? I would start looking for broken traces or heavily corroded IC legs.
The lack of a startup chime could mean that the audio circuitry itself is damaged, which is quite common effect of cap juice corrosion. Or it could mean that the CPU isn't able to load the self test from ROM for some reason (again, probably broken traces etc.)
The lack of a startup chime could mean that the audio circuitry itself is damaged, which is quite common effect of cap juice corrosion. Or it could mean that the CPU isn't able to load the self test from ROM for some reason (again, probably broken traces etc.)
I'm at this exact place with my IIsi. I've documented the restoration over on 68kmla, and there are some suggestions there that I need to follow up on.
The cap leakage seemed to be minimal. There was no battery bomb. I will take a look for broken traces around the ROM maybe. I did try a ROM simm from my se/30 and jumped the pins to use the rom simm but there was no change. However I did not both the 12v line and 5v line were a little low.
The IIsi also has RAM soldered directly to the board. You might want to check it and the associated LS chips. I’ve seen cap leakage do bad things to those logic chips.
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