08-24-2018 10:37 AM
When I start up my printer it’s just write L4EF4K. And I can not to anything, it’s just stay there in the display.
i have just bout this printer. It’s not new, it’s from 2014
08-24-2018 03:10 PM
I found four printers in the model category "HP DesignJet T520 36-in Printer"
One was available in September 2012 (CQ893A), two were available in 2017 (CQ893B and CQ893C), and one is available in 2018 (CQ893E).
None of the documentation for the printer model series includes the error message (L4EF4K) you are seeing on your printer display.
Checked the following documents:
Please read the documents: Double-check what you have tried / what is available to help.
In general, error messages on the printer display can indicate the printer might be
- in need a reset
- is misconfigured
- not connected to network / computer
- plugged into a surge protector (plug printer into a standard wall socket, at least until it works -- surge protectors and backup battery units can interfere with the printer's function)
If the issue is due to lost communication
If the issue is due to the printer needing a firmware update
Download and Read the PDF file instructions:
Then, find and install the correct firmware update for your printer.
The firmware packages are available on the printer's Software and Driver Support page.
- Open category Firmware
- Scroll down and look for the correct "Revision" of firmware for your printer.
- Open the Details page, read all the instructions, then proceed with the update.
Contact HP Technical Support
If your printer is one of the newer models (B, C, or E), it might still be under warranty.
“Everywhere” Contact Information
Select your region and follow the prompts
Option: Contact HP Technical Support - Regions
USA / Canada
- Submit information online: HP Customer Support - USA / Canada- Contact
- Sign in or continue as a guest
- For faster support, submit information online HP Customer Support - UK- Contact
- Contact Phone: Contact HP UK – Phone Assist
Reference and more resources
Printer Homepage – “Things that are your printer”
Drivers / Software / Firmware Updates, Videos, Advisories, How-to, Troubleshooting, User Guides, Product Information, more
Thank you for participating in the HP Community Forum.
We are a world community of HP enthusiasts dedicated to supporting HP technology.
08-28-2018 02:39 AM
If any body face the below related proble of HP designJet T120/t520 printer relted, you must follow the below process:
At first try to follow the below steps and get it fix by :
- Connecting the printer to another outlet
- Repacing the power cable
- Replacing the Main PCA (If you have replace Main PCA, it will solved the issue.)
Also try to Isolate the printer by removing any connectivity cables, printhead
Try removing the ink cartridges, printhead, paper, replacing the power cable and another power outlet. If you still have the problem, please replace the Main PCA (P/N: CQ890-67097)
N.B: Part No. CQ890-67081 is an older revision.
Main PCA - T120: P/N: CQ891-67013
Main PCA - T520: CQ890-67023
It is my understanding that the new Main PCA should come with the USB with the FW. Make sure it is there before installing the new main PCA.
If problems with the FW, will not recommend you to use the old USB with the firmware again.
If not covered under warranty you may replace Encrypted chip which is failed on the mainboard inside the printer you can buy it on ebay/other's source:
I hope that answers will support to concern adequately. Let me know! Good luck
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