Xerox Phaser 7400DN

[lola88]

I am having trouble getting a reset for new black image unit install. Have tried manual reset in service menu. Have tried 2 different sealed brand new units. Have tried different drum unit in black spot and put black unit into yellow spot no change still get replace black image unit message. Any help or ideas would be appreciated.

[Exok]

Re: Xerox Phaser 7400DN

It sounds like you might be having trouble with the black image unit crum reader. I would start with inspecting the crum reader and its harness, reseat connectors.

[lola88]

Re: Xerox Phaser 7400DN

Can you give me a idea where this Crum Reader is located. I was finally able to find a parts list and don't seem to see that listed. Under that name anyway.

[JustManuals]

Re: Xerox Phaser 7400DN

This Parts & Service Manual can now be purchased for $12.77 and downloaded immediately after payment from:


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Paul@justmanuals.com

[lola88]

Re: Xerox Phaser 7400DN

Anybody else have any thoughts or prayers for me.

[yourownfree]

Re: Xerox Phaser 7400DN

have you resolved this issue yet? I have the same issue and am looking for answers. I am not very talented on this machine and am going to dissect the service manual tonight just for this problem. I am not sure how it reads the drum but I do notice a reflective sensor flag on the drum unit which rotates the contact on the rear of cartridge and 4 in front. I did check the cartridge in another unit it is good. The sensor is good. I am getting a change back at the main board the sensor board is plugged into. I am assuming it is similar to a dc controller on a canon machine. So if you have not resolved that wont do me much good and looks like nobody else had a good answer as he did not follow up. With that said I will try and resolve this if I don't hear back or get any resolves.
Thanks for looking.

[Mr_FixOK]

Re: Xerox Phaser 7400DN

This can be multiple issues. Is the actual error "replace Imaging Unit" or "install or reseat Imaging Unit"? First check and see if there are any other issues with the machine ie. paper jams, doors ajar, consumables not fully seated etc. as the message queue can get stuck. Then make sure that the Imaging Unit contacts are clean since toner contamination is rampant on this model. You say that you have the svc manual so follow the RAP's for checking the two error messages listed above. You can see if your counter reset functioned or not. Check the Imaging Unit fuse and the LVPS supply voltages. You should do an NVRAM reset and be prepared to replace the engine control board and or NVRAM chip.

Good luck

[yourownfree]

Re: Xerox Phaser 7400DN

This can be multiple issues. Is the actual error "replace Imaging Unit" or "install or reseat Imaging Unit"? First check and see if there are any other issues with the machine ie. paper jams, doors ajar, consumables not fully seated etc. as the message queue can get stuck. Then make sure that the Imaging Unit contacts are clean since toner contamination is rampant on this model. You say that you have the svc manual so follow the RAP's for checking the two error messages listed above. You can see if your counter reset functioned or not. Check the Imaging Unit fuse and the LVPS supply voltages. You should do an NVRAM reset and be prepared to replace the engine control board and or NVRAM chip.

Good luck

Thanks for the ideas, much appreciated. Good question about either install or replace. It says replace imaging unit. Yep I did the nvram. Still trying to find time to look over the sv. I did not have the sv when I first looked at the machine and it was in a remote location. Once I review it I am sure it will become more clear how it sees each unit. All contacts are clean and in position properly. I know sometimes there is a quick fix for somethings on certain machines not noted in the book. I am busy on wide format problems now, I hope I can get to this machine by the end of the week. Let you all know what I find.