You can reset the Master Code for a LYNX Touch System by accessing programming using the system's Installer Code and then choosing the option to reset the Master Code. This will reset the Master Code back to its default of 1234. You should change the Master Code after resetting it. When a user inherits a Honeywell LYNX Touch System from a previous user, they will often not have the Master Code for the system. Fortunately, it is possible to reset the system's Master Code back to its default of 1234. This will allow the user to access the Master Tools Menu if needed, and it will give them access to the main code that should be used for arming and disarming the system. After resetting the Master Code, you should change it from its default of 1234. This is important for the security of your system. If you know the Installer Code for the system, then the easiest way to reset the Master Code is to use the Installer Code to enter programming and choose the option for resetting the Master Code. The default Installer Code on a LYNX Touch System is 4112, and the code is usually kept at the default. However, it's possible that this code was changed from its default. If you do not know the Installer Code, then you can still get into programming to reset the Master Code by using the backdoor method. This will require powering down the panel completely and following a series of specific steps to get into programming. The following steps apply to any Honeywell LYNX Touch System, including the L5100, L5200, L5210, and L7000 Systems. Complete the following steps to reset the Master Code back to 1234 on a Honeywell LYNX Touch System: 1. Get into programming. If you know the Installer Code for the LYNX Touch System, then the easiest way to get into programming is to start from the main system screen and choose Security > More > Tools > enter the Installer Code (default 4112) > Program. This will put the system into programming. If you do not have the Installer Code, then you can get into programming using the backdoor method. That process is outlined in this helpful FAQ. It is strongly recommended that you take the time to change the Installer Code back to 4112 while you are in programming. You should also make sure to always choose YES when asked if you want to allow the installer to reenter programming so that you do not become locked out again in the future. 2. Reset the code. Upon entering programming, press the down arrow on the right side of the screen. Then choose the Reset Master Code option in the bottom-left. The system will ask you to confirm. Select YES. This will reset the Master Code for the system back to its default of 1234. No further action is needed. Then press the return arrow in the upper-right corner to exit programming. Choose YES when asked if you want to allow the Installer to reenter programming. 3. Change the Master Code. Right now, the system Master Code is at its default of 1234. You will want to change the code for security purposes. From the main screen of the system, choose Security > More > Tools > enter Master Code (which is 1234) > Users. You will enter the User Management Menu. Click on the Master option in the upper-left to highlight it. Then click the Edit button in the bottom left. Click on the appropriate field to edit the code. Enter a four (4) digit code that you can easily remember, but will be difficult for others to guess. Click Done when you have finished. Save your changes by pressing Save in the bottom-right corner.