915Is ECU ISSUE

hi Gene

If the engine is running the ECU is functioning.  The issue sounds more like a communications error between the engine and the Garmin.  Check your connections at the HIC connectors would be my first guess.  There are a few people on the forum who are good at the electric side of the 915 and perhaps they can offer more help.

Cheers

Gene,

Are you also getting a lane warning light, or are both lane lights off (normal)?

Both Lane A & B lights are Red and do not go off. 

With both lanes in fault, and no indications from any engine (FADEC) instruments, I'm wondering if your battery voltage is going low when you are starting the engine, and the ECU is picking that up as fault on both lanes. If you have not already done so, try cycling each lane after the engine has been at 2500 RPM for a few seconds?  At that RPM the alternators switch, and alternator "A" powers all engine functions and alternator "B" is assigned to the airframe electrical system. If the lanes clear after cycling them then maybe it's a simple voltage problem.  

Will try that in the AM.  Charging the battery now. Good suggestion.