I know this is an old problem. But the first time I have run into it. So far I have replaced the cdims, the mainboard memory and the harddrive. Same symptoms still. Machine turns on and "program loading" until eventual blue screen with the error message CFB31. We have ordered a new main board. Firmware will no flash. For the unusual aspect. When the control panel displays the "program loading" message the bottom third of what looks like a cd is missing. Hope the main board fixies this. Any other ideas to watch for? I appreciate the help.

HDD?

Sorry I meant after replacing the HDD did code go away after turning off and on? I've had this with HDD's that were over 80gb

Same sypmtoms after replacing all of the mentioned parts. HDD was replaced after all the other parts. Next is the main board. Funny thing is if I put paper in the doc feeder the sensor it senses paper. Lift the doc feeder and the scanner lamps rehome.

Just to add a quick note. The main board fixed the problem. Went back to the customer today and went like clockwork.

Had the same problem . The main board had a small cooked ic above connector yc25 .According to TS most of the time a cfb31 code is a com problem between the op panel and main board. Cfb30 is a HDD problem.
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