II have a normal spark switch connected on slot N in the mercury SRS , switch on channel 12 in my Futaba 18 Mz .
+ 100% and - 100 % on the switch , a 3 way switch . No problem the light goes on and off .
When i connect the new spark switch pro in the same way, no light, the manual of the spark switch pro sais ready for use .
Can you tell me what is wrong,