I know this is an old thread...but maybe another newbie like me might find it helpful. I have a 2440 with fuel and water temp gauge issues. I ordered the Owner Manual and Technical Manual but needed to work on it right away. My local John Deere dealer was kind enough to print out a copy of the schematic from the Technical Manual for me to use while I waited on my own copy. I am sure it is copyrighted or I would share it with the forum. Check with your local dealer. Also, you may find it helpful to refer to the JDParts on-line catalog. It shows the wiring harness and gives a pretty good look at general location of all the sensors. You will likely need a good Volt-Ohm-Meter to go much further.