Ok, Shy Torque might be right. I am bored, been here since 1100 on a Sunday for a 1200 departure, its now gone 1500 and some of the pax still stuck in LOS I've been told. Going to be 1700 I bet before the job is on.
So went down and turned on the BAT. After the initial start sequence on the N1's with both usage lights and all digits showing '8' s, I covered the test cell to see
drNO for about 2 seconds then rANO.
Subsequent tests with the power still on gave the previous rANO.
Now here's a guess.
drNO might mean dDrNotOperating. Yes? The DECU was still going through its 10 second 'wake up' and it was during that time that this code was displayed.
Using some of the same lose logic, might rANO mean referenceAlternatorNotOperating.
Checked the 2S1 Maintenance Manual, zip.
Sprocket......nope, the ginger beers say there is no battery.
And yes, I agree with all you that are shouting.....get a life!