Communication Manager: DIG-LINE test 16 aborts, error code 3, and test 17 aborts, error code 5

Repair wiring at the jack.  If that doesn't fix it, move the digital phone (DCP phone) to the closest point to the cross-connect for the port that the station is assigned to. If the test fails there, too, make sure that the wiring is good to the digital port. You may also connect the phone to a known-good port. If the phone works there, the port is bad, and the circuit pack should be replaced. If the phone doesn't work there either, replace the phone.