Lane A and B check after start

The traditional reason for a run up to check whether both ignition systems are working does not apply the red lights do that. In effect the ECU's are constantly checking both ignitions and will let you know. So why do it ?? I suppose it proves that either ECO can run the engine but again they self check constantly....

So I struggle to find a good reason to do it....but of course I still do !!

Hi Glenn,

What red lights are you talking about?

Jim

The Lane A and B warning lights on the panel. Usually red, could be amber or "other," I suppose.

Hi all

The ECU has 2 seperate sides.  Lane A and B.  They are very different in what sensors they read.  One thing to note is that each controls one set of spark plugs and one set of injectors.  The run up and check are for you to note any problems.  This is done after both generators are online.  (you have to get RPM to above 2500 to excite the second side to function and then synchronize.  

Think of this like the Mag check in a conventional engine, it is just to verify everything is working correctly.  Depending on what instrument package you have it could be very important.  Not all are fancy like a Garman for example.  

The reasons for each call-out check, found in your operators manual, are very clear. 

Cheers

Thanks all.  Jason, those warning lights are not installed on my aircraft.