208 Rockwell Automation Publication 1756-UM001M-EN-P - February 2012
Appendix A Status Indicators
OK Indicator
The OK indicator shows the state of the controller.
1756-L6x Status Indicators
The 1756-L6x controllers have status indicators on the front of the controller at
show the state of the controller.
Table 61 - OK Indicator
State Description
Off No power is applied to the controller.
Flashing red Either of the following is true:
• It is a new controller, just out of the box, and it requires a firmware upgrade. If a firmware
upgrade is required, the status display indicates Firmware Installation Required. To upgrade
firmware, see Upgrade Controller Firmware on page 51.
• It is a previously-used or in-use controller and a major fault has occurred. For details about
major recoverable and nonrecoverable faults, see the Logix5000 Major, Minor, and I/O Fault
Codes Programming Manual, publication
1756-PM014
.
Solid red One of the following is true:
• The controller is completing power-up diagnostics
• The charge of the capacitor in the ESM is being discharged upon powerdown.
• The controller is powered, but is inoperable.
• The controller is loading a project to nonvolatile memory.
Solid green The controller is operating normally.