My C35 brush cutter won't start. I've ruled out fuel and compression. The coil tests good at <1 ohm primary and about 3k ohms secondary. However I don't see a visible spark. Is there anyway to test the solid state ignition module? It's located on the outside of the unit. At $55 + freight it's a little spendy to buy if it's not really the problem. Is there a foolproof way to test for spark? (I've been fooled before trying to observe spark from a plug outside the engine and grounded).