Macintosh Classic not recognising hard drive or floppy disk drive

[dc99]

Unit as has been recapped but still doesn't see either drive on boot up. Both drives are good and work on another mac classic.

Unit can boot into ROM, and again neither drive is visible. It's unlikely both the SWIM and SCSI ic's have failed however looking at the BOMARC schematics I can't see anything obvious that would result in both drives failing to be seen by the computer.

Any suggestions?

 

[finkmac]

this sounds like broken traces somewhere. did you beep out the scsi lines with a multimeter?

 

[dc99]

I did check the traces but will check again. It just seems like more than a coincidence that both the fdd and hdd are not being seen.

 

[falen6]

id have a look at the chips related , that are close to the caps that leaked ...... look at them all very carefully......their pins and pads .... look for any discoloration .......... reflow them all