Lane A Fault Light On Steady 912iS
Beautiful day today to go fly. Did preflight, sart-up, oil warmed up to above 120 on taxi to run-up area then throttled to 4,000RPM and switched off Lane A - all good - then switched back on and the light remained illuminated. After cycling Lane A again the light still remained illuminated.
This being the first time for this to occur I was curious if the engine would just shut down if I flipped off Lane B with Lane A light on. Engine continued running but running slightly rough. Flipped Lane B on again and the Lane B fault light went off while Lane A remained lit.
I sat and pondered a minute since with both lanes flipped on the engine runs smoothly and coolant temp, oil temp and oil pressure all remained in a good place. It was then that I decided I would use the engine sensors to help me narrow things down.
When I flipped off Lane B the EGT for cylinder 3 dropped off. Flip on Lane B and the engine smooths out and EGT for cylinder 3 returns to normal.
I pulled into the hangar and let the engine cool down as I removed the top cowling and went to lunch. Came back, pulled the top spark plug (Lane A is top plugs) and it appeared to be clean and functional. All spark plugs were replaced just 3 flight hours ago during annual condition inspection. Of note, I replaced with NGK spark plugs instead of the Rotax plugs. Even though the plug appeared to be fine I replaced the plug with another NGK (16 NGK plugs came with the RV-12iS when I purchased) off the shelf. Started up only to discover same results as from the previous run-up.
Any suggestions of where to begin troubleshooting?
“Never feel sorry for a man who owns a plane.”
-Charles Morse (Anthony Hopkins) Movie - "The Edge" https://youtu.be/dJD0lB4zRes
"...except during the month of Annual Condition Inspection."
-Me (in the hangar)
"My first wife didn't like airplanes." - Gordon Baxter