ECL power control cables
I can't find anything that suggests the ECLS can't control the FMM even in auto mode.
Note
Each engine trim beep switch controls the respective control lever from MIN to FLIGHT position when in AUTO mode, and from MIN to MAX position when in MANUAL mode
Not aware of the logic behind it.
Note
Both engines control levers should always be operated through the beep switches located on the collective control. They should be operated manually only in case of failure of the remote control (ECL FAIL caution message), or before starting, to position the lever to FLIGHT.
if electrical power is lost to the collective auto/manual switches, the solenoid should release and revert to manual mode.
ELECTRICAL BLACKOUT
Following a dual generator failure, if the batteries discharge completely (electrical blackout) the engines continue to run in AUTO mode: they are controlled by the EEC which is then electrically powered by the relevant Permanent Magnet Alternator (PMA).