Controller Startup Sequence

The 18R2 Controller requires three AA batteries. Insert batteries into the battery compartment on the back of the 18R2 before powering on the unit. Energizer batteries are recommended by COBRA. Three AA batteries will provide five to six hours of operation. If battery life is a concern, install new batteries before your show. COBRA is also developing a lipo battery upgrade for the 18R2 remote.

  1. Insert key into the 18R2 key switch and turn clockwise to the ON position to power on the controller.
  2. The system will perform a startup sequence, described below.
  3. The current channel will display, for example, “c00” or “c01,” after the startup sequence is finished; the controller is ready for use. 

When the unit powers on, the following information displays: 

Firmware Version


The 18R2 and firing module displays the firmware version of the device first, such as, “5.1.0.” 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 Figure Out.

Battery Life

The 18R2 displays the battery life range on a 1P scale, indicating a depleted battery with a 1P0 and full battery with a 1P9. CORRA recommends only Energizer AA batteries and has a life of about six hours. The AA batteries power the entire controller including the RF module, LEDs, and 7-segment displays. As the battery level decreases, the amount of transmitting power is not reduced. For example, a controller at P1 has the same transmitting power as a controller with P9.

Note: The 18R2 displays “Lo” if the controller battery level is P3 or lower. If you see “Lo” followed by a 1P value, a channel, and an address, this is informing you a module or other device has a battery level of P3 or lower.


“tSt” displays as the firing module perform the following tests:

LED function – When the key of the 18R2 remote is turned on 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. If Er3 displays, power the system off, then back on and do not press any buttons during startup.

Script Count


The 18R2 displays the number of scripts that are loaded to the controller.

Current Channel


The 18R2 current channel.

Module Count


After the 18R2 finishes starting up, the TEST LED will begin to blink if it recognizes any firing modules or other devices such as the Audio Box. Once all devices are identified, the total number of devices displays. For example, if you have three modules and one Audio Box, the number "4” will display. A 36M or 72M is recognized as only one device.

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COBRA offers a 24-hour support system for on-site emergencies. If you are on a shoot site and encounter a show-stopping issue, please reach out to us via phone at 929-930-6868.