Maxtork
Thanks, sounds similar but with differences.
On both 155 models (B has the 2C1 and the B1 has the 2C2) if there is a loss of signal for which there is redundency, and so no effect on governing performance, the flashing GOV caption is used, with similar logic to what you have described. It flashes because it will be sitting amongst a load of other captions, normally, on shutdown.
If a signal is lost for which there is no redundency and a back up, or retrieval law, is incorporated, the steady GOV caption comes on and indicates there may be some degradation in governing performance. You could still have both channels working though (yes, it's dual channel).
If there are multiple input failures, or somehow the actual FADEC it self fails, and the FADEC can no longer function, the metering valve freezes and the Red GOV caption comes on if you are in a B model (pre back up mod) or an amber FADEC FAIL caption on the CAD if you are in a B1 or a B with the mod fitted. In the first case, that's it, the engine is frozen and will probably need shutting down for landing to prevent overspeed. In the second case, the back up switch is used to operate the EBCAU and a normal landing can be maded without abrupt power changes.