After turning the module key into the ARM position If you press the ARM button on the 18R2, the ARM LED will blink; this means the 18R2 is discovering armed modules. Once the ARM LED stops blinking, the total number of armed modules will display, which means the modules are armed and ready to fire. While arming, you may see address values appear such as A01, A15, etc... This occurs as the 18R2 is trying to discover and arm these devices because they were recognized in TEST mode. If the 18R2 fails to recognize them and continues to display the address, the module is not communicating with the 18R2, out of range, or the key is still in the TEST position.
If the 18R2 is in ARM mode and you want to refresh the module counts and re-arm the devices, press and hold the ARM button for 3+ seconds and the ARM LED will begin to blink. The same applies to TEST mode as the operator can press the TEST button for 3+ seconds to refresh the modules in TEST mode.
Once you see the 18R2 display the total number of expected modules and your ARM LED has gone solid your modules are now armed and your 18R2 is ready to shoot.