Here’s a quick general explanation into diagnostic tools/systems.

There are 6 basic functions for a diagnostic system:

  • Fault (DTC- diagnostic trouble code) reading and clearing
  • Live Value display
  • Editing the car configuration files (CCF)
  • ECU Flashing
  • Executing service routines/manually actuating components (testing function)
  • Initializing, calibrating, or programming new components

Starting with the lowest priced units, even a 50 $ generic code reader will read and sometimes clear the codes on anything that is emissions related (engine+drive train). The downside is that they will not work on all vehicle systems, including manufacturer specific fault codes (air suspension, etc). All other features in the list above are not supported on generic code readers except for a few emission related live values.

The IIDTool will allow you to read and clear manufacturer specific fault code on all ECU’s and give you access to all other features listed above. This is why it is called a complete diagnostic system for your Land Rover.