OfficeJet K5400 blinking pwer and resume lights

[lkeyes70]

My K5400 now has stopped printing and shows simultaneous blinking power (green) and resume (white) lights which ndicate a paper jam.  I've gone over it with a fine-tooth comb as it were, and there is no paper jam to be seen anywhere. Have gone through the paper jam steps here on the HP web site and the vidoes.  Questions:

1. Apart from examining all openings with a flashlight, (front/back/duplexer is there anything else to disassemble (ie. removing the outer case, to be able to find a paper jam? 

2. Is there a service manual for this printer?  

3. Could it be related to a firmware update?  (or lack of a firmware update)?  

4. Is there a mechical switch or sensor anywhere that could be responsible. 

I've had this machine since about 2008, and it has proven to be very reliable...and hate to have to replace it because of something that could be fixed.    Any ideas appreciated.     --- L

[Betty0610]

@lkeyes70

Welcome to the HP Forums 🙂 I would like to take a moment and thank you for using this forum, it is a great place to find answers. 

Since you've already tried all the steps and this is a Hardware issue, for the next course of action, I have sent you a private message, for more details that cannot be shared in a public post.

Please do check your inbox on the forums page for the private message.

Thanks!

Have a great day!

[JMR130]

Is it possible to obtain a service manual for my HP K5400 printer, or an assembly diagram which shows how to remove the plastic enclosure.