"Phone off-hook" HP Officejet Pro 8500 Wireless, Product CB023A

Question

I have a HP Officejet Pro 8500 wireless printer/fax/copier all in one.
The message "phone off-hook" appears on my display. 
I ran the Fax Test and received a PASS for all results.
A few minutes later, a message appeared on the printer/fax display: "Turn power off, then on again". I did so.
This message, "Turn power off, then on again" continues to repeat and after I turn power off then on, the "phone off-hook" displays again. It is an endless loop of receiving these two messages.
I also did the following:
1. Unplugged the telephone fax line from LINE of the Officejet Pro.
2. Unplugged the power cord to the printer.
3. Replugged the power cord to the printer.
4. Powered up the printer
5. After powering up, the message, "phone off-hook" reappears.
I ran the fax test
Run Fax Test:
1. select Tools from HP Officejet Pro 8500 wireless display panel.
2. Select Run Fax Test
Results:
Fax Hardware Test ........................................................ PASS
Fax Connected to Active Telephone Wall Jack ......... PASS
Phone Cord Connected to Correct Port on Fax ........ PASS
Using Correct Type of Phone Cord with Fax ............. PASS
Dial Tone Detection ....................................................... PASS
Fax Line Condition Test ................................................ PASS
3. The message still appears.
My printer description is as follows:
- Model No. : A909G (look inside of the ink access door); Regulatory Model No. : SNPRC-0703-02
- Product No. : CB023A
- Serial No. CN0737R2DH
Is the printer defective? What should I do to correct this problem?
Thanks,
ArtLaw

Answer 1

Hello ArtLaw,
If you have followed all the troubleshooting steps outlined in this troubleshooting article then the only other solution is to have the printer serviced as it may be a printer hardware issue.
Troubleshooting 'Phone Off Hook' Front Panel Messages
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