think starter selonoid is bad have 12v on one side but not the other bypassed it and starter works no spark but when grounded it sparks so im going to get spark plug as for selonoid i dont know if its that or something like ignition switch all fuses are goodcan the switch under the seat go bad any help from anyone would be greatly app.

the starter solenoid wont have anything to do with the spark that just lets the starter get power and turn the engine over ,, what is the engine on ? what kind of mower ? could be a few things causing the no fire problem , hard to help you without knowing what its on , also would help to have the first 2 numbers of the code off the engine ///

reason why its important on the code, no spark could be some things, bad ground, bad switch, which in either case you can try taking the kill wire off..... see if it does it, if its old enough for points and condensor, try new point and condensor (cheap), if its young enough to have a magnetron ignition, coil could be bad, or spark plug wire grounding to the shroud from cracking in the wire (may get by with electrical tape). thats just things for no spark, other then a bad plug.