Combines Fore and aft not working

Have you a connection to the signal valve solenoid. To work any function other than header raise and lower and reel lower, you need to power up 2 solenoids,one of which is the signal valve. It is the 3rd solenoid from the top on the cab side of the stack.You need to connect to it using one-way diodes.

I was just wondering how much it cost for a used system to get your fore and aft working. I bought a 1680 without fore and aft, so I made hand cranks, but it would be nice to control it from the cab. My header is set up for it already.