HP Color LaserJet 9500 Multifunction Printer series - Manual (Page 116)

http://www.hp.com/go/clj9500mfp
100 Chapter 4 – Faxing Rev. 1.0
Sending fax problems
Use this table to solve problems that might occur when sending faxes.
Problem Cause Solution
Faxes stop during sending. The fax machine that you are sending
to might be malfunctioning. Try sending to another fax machine.
Your phone line might not be working. Disconnect the fax from the phone jack on
the wall and connect a phone. Try to make a
phone call to verify that the phone line is
working.