A phone connected to the HP fax (or the same phone line) is using the same phone line as the fax, or a fax handset has been lifted
A credit card machine or other electronic device is using the phone line
A Telephone Answering Machine is using the phone line
The Start Fax button on the control panel was pressed
HP All-in-One and Fax Products - Troubleshooting Phone Off Hook Front Panel Messages
A Phone Off Hook message is shown from the front panel of your HP faxing product. This message indicates that a telephone receiver is off the hook (the handset is lifted) and the telephone line is open.
This message would be expected in the following situations:
Step 1: Check the phone line
Make sure that all other devices that use the same phone line (phone number) are hung up or not actively using the phone line - this includes telephone answer machines and the hand receiver that might be attached to the fax machine. You can lift a telephone receiver that shares the same and listen to the phone receiver and listen to hear if the phone is being used. If you hear anything other than a dial tone, including silence, then the phone line is in use and is probably the reason the fax machine is showing a message.
Make sure the phone line has a dial tone before attempting to fax.
note:If your phone line is used with a DSL broadband Internet service, make sure a filter is connected to the line if you can hear noise when the modem is on.
If phone off hook message continues and you've made sure that the line is active (has a dial-tone), then continue to the next step.
Step 2: Reset the printer or fax machine
Reset the printer or fax to clear any stuck fax jobs or problems related to the printer faxing hardware.
Disconnect the power cord from the machine.
Wait 60 seconds.
Reconnect the power cord and wait for the printer/fax machine to fully start up and become idle.
note:If using ISDN or PBX, detach the HP printer or fax machine from the ISDN A/D converter or from the PBX and use a 2 wired cable between the ISDN A/D converter or PBX.
- Try to fax again:
If the Phone off hook message no longer appears, you are done.
If the Phone off hook remains, continue to the next step.
Step 3: Replace the LIU or service the product
If the problem still exists after performing the steps above, the line interface unit (LIU), the part that the phone cord plugs into, may have been damaged by an electrical surge. The LIU (if a separate component) may need to be replaced or the HP product may need to be serviced. Contact HP Support for further assistance.
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