cub cadet 2166 coil wire question........

I am trying to determine if my coil is bad. My engine will start and run for a while, and then shut down and has no spark to the plug. I am not sure if it is a safety switch or a bad coil. I am able to remove the battery and move the shroud enough to access the coil. I want to temporarily remove the wire that shorts the coil and see if the engine stays running. There are 3 wires besides the wire to the spark plug. A yellow wire and a brown wire plug into the top of the coil and there is a wire attached to a ground lug that is attached at one of the coil mounting screws. I sure would appreciate any help. My guess would be to remove both the yellow and brown wires, but i'm not sure. Thanks Chuck