Nothing is immediately coming to mind. A few more questions for you that might help narrow things down: Have you dropped the relay cover that the fuse block mounts on to inspect for damage yet? If not, do so and let us know what you find. Check the connections on the control card well. What do the "Fuel" and Power Use gauges do when you move the control and the relays chatter. Does the PTO still work? How about the lift?
Also, please post what sub model of E15 you have (AA, BA, etc.). This can be found on the serial number plate as the model number suffix.