A320 Mode Select fault

[Flo121142]

Hi,
yesterday I had some strange behaviour of the fuel system. The aircraft was dispatched with one Wing Tank Pump (R TK Pump 2) inoperative according to MEL. After departure I noticed that the fault light in the Mode Select p/b was illuminated, but we didn't get the corresponding ECAM. As the flight was relatively short we didn't have any fuel in the Center Tank. The captains opinion was that this is a false indication and I tend to agree - however, can somebody shed some light on this issue? Has someone experienced something similar already?

[Zippy Monster]

The "fault" light on the fuel mode selector push-button can appear to be dimly illuminated when it is in fact not. I can't remember the exact technical reason for this but it is a known peculiarity of the overhead panel. I have seen it reported in the technical logs on some of our aircraft by crews who didn't/don't know this - the response from the engineers is along the lines of that it is known and it is no concern.

Next time you see it, put the annunciator light switch to "test" - you will be able to see the difference between an actual "fault" annunciation and the dim illumination when it is actually off.

[Flo121142]

Thanks for your answer, in our case the light was indeed very dim compared to the other lights on the panel, so propably your explanation is the correct one...