Should you suddenly find functions missing from your 500 series instruments that were previously there, it is possible that one or more functions have been disabled. To remedy this situation, follow the instructions below:
Scroll down to "Configuration" from the main menu screen and press the enter key
Scroll down to "Active Functions" and press the enter key
All functions that you wish to use should have an arrow in front of them
Scroll down to the function(s) that you wish to activate, and press the enter key
Each press of the enter key will toggle between on and off
After setting the functions as desired, press the X key to return to the main menu
Once you have set things as desired, it is possible to lock out the configuration menu so that it cannot be changed. Many customers have found this a useful feature.