As technology evolves and machines get more com plex, repairing equipment becomes a very complex issue. Long gone are the days where you would – listen in, hear a rattle, grab a wrench and fx the problem. Today, there are multiple complex connected systems, and the newer and more evolved the vehicle, the more complex the system. Just take the John Deere 9R Series: it has over 10 different electronic control modules that require reading codes, clearing codes, calibrations and so much more if the owner wants to keep the equipment in top condition.