Press the "*" (asterisk) key on the main control unit and tap the "<" or ">" button until "Access Codes" appears on the display.
Press "5" or "*" to enter the code menu. Enter the current master code using the number buttons.
Press "*" when "User Code 40P" appears on the screen. Tap "<" or ">" if it doesn't appear after the previous step.
Press "*" confirming you want to change the master code. The display shows "Enter New Code."
Enter a new code using the number buttons. The code must be four digits long unless your system was programmed differently by the installer. Only use numbers 1 through 9 in your code.
Press "#" when you are finished. The system beeps three times when a new code is successfully programmed and the display shows "User Code 40P" again.
Write the new code in the "System Information" portion of your instruction manual and store the document in a safe, secure place. The new master code is now ready to use.