LaserJet MFP M479 Fax Line Busy Signal

[jazzybob]

I'm installing a new LaserJet MFP M479 and when I tried to install the fax line it said that the LaserJet was not connected to a line. The line is share with a phone & answering machine and when I took the cable from the LaserJet and connected it to a phone I got dial tone. But, when I connected it back to the LaserJet and picked up the phone Line, I got a fast busy signal. If I unplug the phone line from the LaserJet, I get dial tone again. I turned the printer off, but still get the fast busy signal.

[Mark202]

I am also experiencing the same problem.  I have the AT&T Uverse phone system.  I have a dedicated fax line.  The light on the AT&T modem is blinking green.  When I dial the number and fax line is connected the line is busy.  When I unplug it from the wall and dial it goes thru. 

[jazzybob]

I actually figured out the problem. On the back of the printer in the upper right hand corner, there's a cap that covers the Digital connector for those of us who have cable modems for our phones. Once I connected the phone line there, it fixed the problem.