36M & 72M Startup Sequence

Firmware Version


The firing module displays the firmware version of the device first, such as “5.0.2.” All devices synced together must use the same firmware version.

To learn more about firmware versions and how to upgrade your system, at no cost, please see Firmware Figured Out.



“tSt” displays as the firing module performs the following tests:
Cue responsiveness – Tests the responsiveness from each cue, ensuring each firing MOSFET turns on and off. If any cue is unresponsive, the system will display Er1 or Er2.

LED function – With the key in the TEST position only, the red and green LEDs will flash briefly.

Shorted/stuck button – During the self-test, if any button is pressed a false-positive to the shorted/stuck button test will occur, and error code Er3 will display.

For more information on 36M & 72M self-test error codes and how to resolve, see the Error Code Reference Guide.

Main Display


Used to display the module's battery life, address, bank & associated channel, and signal strength. For more information, see 36M & 72M Power On & Startup Sequence.

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