LEM...the start switches were on the "CONT" position at the time the light came on.We advanced the thrust levers several times and the light went out.However when the T/L's were pulled back to idle the light went on again.
On your second question the answer in NO...i wouldn't fly the machine if the problem was there after the run up.
DOC..the fellow engineer on board suggested the same thing that the conditions for the light on are the ones you mentioned.
However i had a disagreement with him(not that i doubt the engineers) because the books for the 737 mention that the engines have 2 idle speeds (22% on Ground and 32% in FLT) and whenever the idle speed of the engine goes below 32% in flight the light comes on.So it was pretty clear for me !
My question is..." are there any operational restrictions when this light comes on"...The MEL is not of any help !
The method for the run up was pretty simple....started both engines and then the engineer pulled the A/G switch CB !