Apple Lisa Chirping

[decisive1]

Hello all, I've owned this lisa for a few years and now starting the rebuild process. When I power on the lisa I am getting a chirping from the power supply immediately on plugging in the power. Where is my starting point in troubleshooting? I was reading this may be an issue with the IO card? Appreciate any input and happy to meet everyone here. Dylan

 

[lisa2]

You have an electrical short somewhere in your Lisa. Try pulling out the IO card and see if she powers up then. If she does, then it's an issue with the I/O board. If it's not the I/O board, then try unplugging everything you can ( disk drives, RAM cards, expansion cards, etc. ) till she comes up.

 

[decisive1]

Thanks for the tips there, the process seems similar to traditional computer troubleshooting processes. I guess I was bit hesitant with the Lisa because I wasn't sure what might damage it (or blow up in my face). Really I was afraid of it catching on fire. My Lisa was in pretty bad condition, leaves inside and motherboard covered in some muck like being in a garage for 20 years. I spent a good number of hours cleaning before I would try and give it any power. I've cleaned it with isopropyl alcohol and looking a lot better, but really I'm unsure on some of the boards.

Reseating the cards after cleaning and some of your input I was able to get the power switch light to turn on (chirping is gone). Then removing some cards I am from time to time getting activity from the floppy. The screen also eventually turned on with black screen and few grey lines. Overall its still pretty quiet when I press the glowing button. I'm happy to see it glowing at least

I think the next step is to get a motherboard which I know is working and have a solid place to start now that I see some life out of the PSU. Thoughts guys?