"DR Signal Off" alarm (often alarm 086 on a Fanuc)
This alarm occurs when the CNC checks the data ready handshake line (sometimes called DR or DTR) and finds that the device is not ready. There are a few possibilities for this problem depending on how your cables are wired.
Verify that your port is OPEN in the DNC software.
If your port says the status is CLOSED and will not open, view the separate solution document titled "Troubleshooting a port that will not open".
Verify that you have the correct COM port selected in the DNC configuration. A common problem occurs when moving computers. On the old computer, a serial hub may be using COM11-COM18, while on the new computer it is assigned a different range. Until you select the new COM port number corresponding to the physical port where cable is plugged in, the machine will be unable to communicate
Verify that the cable is plugged into the CNC and the CNC is connected to use the port you are plugged into because the CNC may have multiple ports, if you are plugged into port 1 externally while the parameters are set to port , you will get an alarm.
Verify that the cable is wired in accordance with one of the Fanuc compatible wiring diagrams in the separate document titled "Standard wiring diagrams".