Ricoh MP C2550 with SC491 after a repair

[mntech]

Hello,
I had a tech go out to replace a sensor in the paper exit section(just past the fuser).

He had to remove the integrated finisher, small front cover, and exit section to get to the sensor, after he replaced the sensor the machine codes out with SC491 (High voltage power: Drum/ development bias output error), and it seems way to coincidental that the error came right after he did repairs. He double checked his work and took it all apart and checked everything, and I also went out and did the same thing.

We cannot find any problems with the section he tore apart, no pinched wires, misaligned parts, etc, and this error code doesn't really have anything to do with the section he worked on.

I've tried a replacement for each drum, but I do not have any dev units, transfer unit, or the high voltage board, and am wondering what you guys think I should try next.

I've inspected each dev/drum unit, the transfer belt unit, the bias transfer roller unit, tried cheating the door with the transfer roller unit/door open, checked grounds on each drum. Tried removing the finisher and disconnecting the exit assembly( since that's what was repaired last)


I really wish i had a parts machine so we could just start throwing parts at this machine but I do not want to order a part unless I know it is faulty.


Thanks,
-MNTECH

[sandmanmac]

When a problem occurs only after a tech has been working to fix another issue, all we can do is guess.
My guess?....probably took out the CB Power pack during the service. Probably from not powering down/unplugging before disconnecting harnesses (even though he'll never admit it )