I'm having deja vu with this thread, because I owned a Stiga ride on mower one time and all of the things being discussed here are the same issues I had with mine.
In fact I found my original diagram and it is identical to the one provided.
Once again I must urge you to check the voltage and amps rating on the switches. If you take one of the switches off it will be written on it somewhere. The original electronic circuit plate is designed to make everything work by providing a greatly reduced electric load though the switches and circuits, but allowing the full volts and amps from the battery where it is needed, i.e. to the starter motor. If you bypass this in any way you will almost certainly overload the switches and they will begin to malfunction.
However I am not sure if this will still be the case if you do away with the battery altogether. My feeling is it probably will still present a problem, given enough time. You would have to check the rating on the switches and match this against a measurement from a voltmeter and ammeter while it is running. The circuit board was designed to reduce the output to some components while allowing full electric output to others.
The wiring inside the switches is very fine and delicate and not designed to take a full load from a battery. You need to treat these as if they are a fuse. I know this from my own bitter experience. I can only state that I overloaded my switches after just a few hours of running the mower and then they began to malfunction.
Last edited by vint_mow; 01/04/18 09:33 PM.
