Help needed with LC II diagnostics

FortyTwo

New Tinkerer
Nov 24, 2021
7
4
3
Indianapolis, IN
Hello all, I have had this LC II for many years and it used to boot and run but has since stopped working. When I flip the power switch on, the case fan turns on full speed and a blank gray screen appears, but nothing else. There is no hard drive activity, no "Welcome to Macintosh," no startup chime, and no Sad Mac. When I flip the power switch off, the speaker crackles, which tells me that the 30-year-old caps haven't killed the sound capability completely. I have tried starting it with and without a fresh clock battery, but it did not seem to make a difference either way.

Does anyone have any thoughts about what I should try yet? There is a little bit of cap-related grunginess near the PDS. I knew that old caps could affect the sound, but is it possible that they would also affect the computer's ability to even access the drives and boot? Any insights or advice would be welcome!
 

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jajan547

Active Tinkerer
Mar 25, 2022
732
295
63
North Carolina, USA
PRAM reset first this sometimes takes anywhere from 1-5 tries on LC's (command + Option + P + R while booting). Also the SCSI cable is unplugged in the photo. Let me know if any progress happens after you try this.
 

eric

Administrator
Staff member
Sep 2, 2021
939
1,535
93
MN
scsi.blue
As @jajan547 said I'm pretty sure it's just a PRAM issue - I had the same thing happen and spent a few hours debugging till I put a fresh battery in and it booted right up. (IIRC)