Here are some steps you can try to resolve the issue:
Clear the jammed paper: Open tray 2 and remove any jammed paper. Open the rear door and look for and clear any paper present or obstructions in the paper path. Open rear cover. Clear Jam. Close the rear door to allow the printer to attempt to clear the jam message.
Check the fuser unit: If clearing the jammed paper doesn't resolve the issue, it's possible that the paper is stuck in the fuser unit or that the fuser exit sensor is broken. In this case, you will need to remove covers, flat bed scanner, and fuser to check for any obstructions .https://www.youtube.com/watch?v=Lz9cTnbuDbw
https://www.youtube.com/watch?v=MxVyWqGeBgQ
If these steps don't help, I recommend contacting HP support for further assistance.
If you use an HP printer, you might sometimes encounter offline error issues. If you want to know why HP Printer offline, how to fix it? Then follow this post. The offline error can be due to outdated drivers, connection issues, or a settings error. To solve this issue, first, ensure that you have downloaded and installed all of the updates for the Windows OS and check you have set your printer as a default printer, and check whether the device connection is made properly.
https://connectmyprinter.com/how-to-fix-hp-printer-offline-error/
49.XX.XXExplanation:
A critical firmware error occurred.
49 errors are unrecoverable exception errors in product firmware. When a 49 error occurs, the user sees a 49.XX.XX message on the control panel (where XX.XX is replaced by a combination of numbers and letters). A 49 error might happen at any time for multiple reasons. Although some types of 49 errors can be caused by hardware failures, it is more common for 49 errors to be caused by printing a specific document or performing some task on the product than it is for a hardware component to be at fault.
Most commonly, 49 errors occur when a product is asked to perform an action that the product firmware is not capable of and might not have been designed to comply with, such as:
· Printing files with unsupported programming commands.
· A unique combination of user environment and user interactions with the product.
· Interfacing with a third-party solution that was not designed to work with the product.
· Specific timing, network traffic, or concurrent processing of jobs.
Each of these interactions could cause the product firmware to initiate an action that the product cannot accomplish. In situations like this, the product might present the error if it has no other option. When these errors occur, the only way to recover is to turn the products power off and back on.
NOTE: LaserJet formatter PCA's are rarely the root cause of 49 service errors. Please do not replace the formatter or Flash unless troubleshooting has identified the formatter as the root cause.
I suggest that you try to upgrade your printer's firmware and then try doing a FULL NVRAM Initialization .
THIS TYPE OF PROBLEMS ARE FIND GENERALLY IN LAPTOPS AFTER A TIME IF YOUR LAPTOP IN GURANTEE PERIOD THEN . TAKE IT TO THE HP CARE & IS NOT THEN GO TO HP OFFICE & BUY A NEW BATTERY OF YOUR MODEL NO...........
It seems you have done all the troubleshooting yourself. You can't do a full factory reset, because you can't see the screen. You either have an internal power supply unit failure or a control board failure. Neither are really home repairs. A new one is $147, or you can take it to an HP Service Centre. I am sure not to answer you wanted but it has failed.
Here is a Troubleshooting Manual. HP always do things in style! Low-voltage power supply on Page 34.
Laser Pros Internationalhttps://www.laserpros.com > img > hp-manuals
If the hardware or software configuration has not changed or the problem is not associated with any specific software, see the complete service manual for this ...
166 pages
Here is the Service Manual. It looks like the power supply PCB is behind the button. The main PCB is on the right side above the cassette.
Question edited for clarity and toss in some CAPS
Unplug it for a couple of hours. Press and Hold the On button for 2 minutes and plug it back in. That _should_ make it lose its memory by dissipating all internal energy.
The fuel mixture screw only regulated the air and fuel at tick over. normal running is governed by the main jet needle and slide. Check spark plugs, clean carburetor and check timing. Also check for manifold leaks
An air fuel mixture screw is a special screw on an engine's carburetor that controls how much air mixes with the fuel. Adjusting this screw changes how fast or slow an engine idles and how smoothly it runs.
Question edited for clarity.
'OfficeJet Pro', is a series of about 40 printers and you give no clue which one you have!
Here are the Service Manual suppliers.
https://www.google.com/search?q=HP+Officejet+Pro+Printer+Service+Manual
The search query for this is
HP OfficeJet Pro (model) service manual
..
