The only true test is to try another unit, there are very expensive testers out there,but if there is no spark on the machine the unit is bad. Some early ignitions were standard coils and had a de tachable Magnetron pick up pressed between the legs of the coil, this can be replaced rather than the whole unit. Always disconnect the earth cut out wire when testing for a spark, this will rule out any switch problems.
Husqvarna man, January 2010
