Participation in the Solihull Society 2008 Land Rover National Rally was an amazing experience. Time and time again, interested Land Rover owners would approach my vendor tent and tell me about their problems with the Discovery II ABS. This prompted me to begin investigating the most common problems with the Discovery II ABS. I found out very quickly that the ABS system was indeed a source of great frustration to just about every Discovery II owner.
The Discovery II vehicles rely heavily on the ABS system to modulate slipping wheels in an off road situation. If an ABS fault condition is triggered, the driver can be stuck without any ABS or TC. A Discovery II without TC effectively destroys any 4×4 traction. Without the TC, the front, center and rear differentials are completely open and nothing will prevent the wheels from spinning. As soon as one wheel leaves the ground, all power will goto that wheel. Usually the TC would apply brakes to that wheel but without the Traction Control System, the Discovery II is rendered almost completely useless off road.
There was clearly a need for some sort of solution. Even the tiniest signal interruption from any of the 4 wheel speed sensors, would result in a ABS fault condition. So I dedicated a good 6 weeks of intense work to a solution. I purchased a used ABS ECU off of Ebay and began to construct signal transcievers that would enable my laptop to communicate. Hundreds of hours were spent researching and just plain old trial and error.
Very quickly I began to do research into the various communications protocols that the Discovery II vehicles employ. Thankfully, the Discovery II series of vehicles followed a very different communications design from that of the older P38a communications subsystems. The Discovery II series of vehicles adhered to a very well documented ISO structured communications framework. This allowed me to very quickly get most of the lower communications layers established and operational.
To make a long story short, the Discovery II ABS system was a much more understandable and much more easily developed communications protocol. This enabled me to quickly develop the ABS Amigo.