Code 4 (short,long,long,short) Engine Speed Sensor. Performance loss.Check to be sure sensor mounted on right hand side of flywheel housing is fully plugged in. and code 10 (short,short,long,long) Proportional Solenoid Valve.No drive in either direction.Contact your John Deere dealer.
I tested the flywheel speed sensor by making sure there was 5 volt in, and then the manual i have says to check between two wires (b and c i think it was) for Hz. I forgot the value it said but it was in specification of the manual at low idle and fast idle. I thought i was moving everything slowly. All functions calibrate out fine except when i get to the end of the throttle pot.