Zhone IMA CS-200 System Reference Manual page 160

Model No.
Running Head
4. At your end, go to the FXS port Main Screen and send a digital milliwatt test tone (0
dBm) toward the CPE. If you still don't receive a signal, check the cabling from the FXS
port to your CPE, and check the CPE itself. If those items are okay, replace the FXS port
at your end.
5. If the FXS port is determined to be faulty, replace it and return the faulty unit for repair
to the location specified by your distributor.
6-12 FXS Ports