Final answer:
The question pertains to an issue in aerospace engineering or aviation mechanics, where an engine start sequence is not proceeding as expected. The problem involves a valve being open, a nitrogen indication, but no rotation or N1 movement, leading to a stop of the start procedure and consultation of the manual.
Step-by-step explanation:
The question is regarding a procedure to address a specific issue during an engine start sequence in an aircraft or similar setting, where a valve is open and 15% nitrogen (N2) is indicated, but there is no "Rotation" call and no movement in the N1 (which could refer to the low-pressure compressor in a jet engine).
The proper response is to stop the start sequence by releasing the start selector switch and referring to the equipment's manual, in this case, indicated as "No Rotation And No N1, Page 2-32 Caution, 840 in PDF." This issue is typically found in the realm of aerospace engineering or aviation mechanics, and the procedure would be outlined in the aircraft's maintenance or operating manual.