HP Laserjet MFP 521dn ADF disassembly

[LTTP]

Hi, i have one of these units that jams and makes grinding noises when users try to either copy or scan a document, i have the unit already dismounted but i cant figure out how to open it to check below the document lever if theres something obstructing one of the gears.

Any idea on how to open this thing? im talking about the ADF ensamble itself.

[Wild Bill]

Re: HP Laserjet MFP 521dn ADF disassembly

It's not going to be in the service manual. They are designed to replace as an ass'y. They do have some parts I think ADF roller kit and that's about it.
If gears are stripped you may be able to get a used one, Liberty parts Team or Parts Now may have them. You could ask for tech support also.

Taking it apart...It's gonna be like a puzzle they have little points where you would pry it open with a small flat blade screw driver. and just have patience... that's all I have for you.

Good Luck!

[LTTP]

Re: HP Laserjet MFP 521dn ADF disassembly

It's not going to be in the service manual. They are designed to replace as an ass'y. They do have some parts I think ADF roller kit and that's about it.
If gears are stripped you may be able to get a used one, Liberty parts Team or Parts Now may have them. You could ask for tech support also.

Taking it apart...It's gonna be like a puzzle they have little points where you would pry it open with a small flat blade screw driver. and just have patience... that's all I have for you.

Good Luck!

Yeah thanks i decided to not wast any time si9nce we have other 2 printers of the exact same model we can use for parts.

Now something weird is happening, first i took just the ADF aqssembly from one of the unused for parts printers and after putting eberything together, the printer im trying to fix gives an error code 17 and it doesnt get past it.

After that i thought well maybe the ADF and scanner bed are one part and are not interchangeable, so i decided to return the ADF to its original scanner bed, and the machine gave now an error like "cant calibrate remove paper jam from ADF" but there was no paper there so i got worried.

So then i use the full ADF and scanner bed assembly from the printer im trying to fix, and put it onto the printer we have for parts, and its giving me the exact same "error 17", finally i put both ADF units with scanner beds on their original printers and now BOTH are stuck one on error 17 the other on error 13.

WHAT THE HELL just happened? do i need to recalibrate, restore settings or something? obviously it wasnt something i did since both machines now have the same error with BOTH ADF-scanner assemblys.

Any help appreciated.


EDIT: Now after many tries the original printer im trying tpo fix is displaying an error at every boot

"The Product is unable to calibrate. Close the lid and remove paper from the document feeder or flatbed"

If i hit thew home button i can bhypass it but whenever i try to either copy or scan it gives me the same error, ive found another thread here with the exact same problem

http://www.copytechnet.com/forums/hp/88561-unable-calibrate-message-display-start-up-laserjet-pro-mfp-m521dn.html

[theengel]

Re: HP Laserjet MFP 521dn ADF disassembly

I have a feeling that either something is being left unplugged or a there's a broken wire. In some of these, the wire harness can get kinked after a lot of use, and when the tech opens it up, he's actually opening a can of worms; something that was fragile is now broken, and the only way to fix it is to replace the ADF and maybe the scanner bed. As far as I know, there's no real way to replace anything except the rollers in these things.

EDIT -

Probably similar to this problem: http://www.copytechnet.com/forums/hp...adf-issue.html

Only I doubt you'd be able to find (or even replace) the wire harness.