Help CenterTo Change the Honeywell LYNX Plus L3000 Installer Code
1) Remove the power transformer & backup battery so there is no power to the LYNX L3000 control panel. “To verify this make sure there is no power to your keypad”.
2) Next, you can power your L3000 back on by first plugging in your alarm backup battery followed by your transformer within 40 seconds and you should see AC or D1 on the keypad.
3) Press and hold * and # for three seconds on the programming keypad from there you should see INSTALLER CODE 20 or 20.
4) Press *20 4112 (You should here 3 beeps) this will indicate that you have successfully reset your Honeywell LYNX Plus L3000 .
Once you have completed any programming necessary you can press *99 to exit the programming mode of the Honeywell L3000.
Note: This method can only be achieved when the system is disarmed, if the system is armed you will not be able to do any kind of programming.