Try this to reset the dialer settings: Using ELKRP change the country code to something other than United States, then change it back to United States. This resets some of the dialer settings.
Also, using the keypad menu 8, 6, 4, check the "Last On Hook Voltage" to make sure you are above 40 volts on the telephone line.
If you get a telephone communicator failure, you will have to get a good communication to the central station before it will go away or recycle power will clear the error also.
You can use the "Butt Set Monitor" mode, keypad menu 8,4,3 "Turn On Butt Set Mode" and listen to the transmission to the central station through a speaker attached to output 1. You should hear dial tone, the telephone number dial, a 2300 hz tone from the central station, touchtone data transmitted, a 2300 hz tone, then hangup.