Why is my Lynx L5100 always in not ready to arm mode?

The L5100 LYNX Touch is a self-contained wireless alarm system that has been discontinued since the release of the L5200 and L7000 models. The touchscreen display must read, 'ready to arm' along the top of the screen in order for you to arm the system. This means the system is not receiving any faults or troubles. A faulted or tripped security sensor means that a door or window is open or a motion detector has been tripped due to movement in its field of view. A trouble can vary between a loss of RF supervision (panel can not see the sensor), a tamper cover has been opened, low battery, loss of communication etc.

A fault is something that can be restored by simply closing the door or window or preventing motion in space. However a trouble requires a restore and a valid disarm twice. For example, if the system is reporting a tamper cover trouble you will need to close the tamper cover and disarm the system twice. You can also go in and out of programming in order to clear a 'latched' trouble. This may occur if you restore a trouble and the system for some reason does not see the restore.

All in all, if your system is showing 'not ready to arm' atop the screen you have a fault or trouble that is preventing the system from arming. From the home screen, you can go into Security > More > System in order to view trouble codes. You can also view faulted zones in the by clicking into Zones in the Security menu.