My 80HP 912 Rotax had a mag check failure at run up.
First mag drop was almost nill, second mag was an erratic and rough running engine. Classic symptom of a module failure. I pulled the 4pin connectors and swapped them, no change. I pulled the ignition leads from the panel and swapped them and was able to swap the failure from mag 2 to mag 1. So I thought I had isolated the problem to the ignition wire from the panel/mag switch.
Figured this was the problem so I ran a new wire and bullet connector from the connection, test was negative. Did the same for the other bullet connector and still having the same issue. I did a continuity test on the switches and both checked out. could the switch be bad anyway? I'm now lost. Ideas?