My 2006 LR3 started throwing HDC, Suspension, and Transmission faults. Also the steering would get heavy. Replaced the brake switch, cleaned all the connectors etc. myself to no avail. Took it to my local independent LR workshop who then started switching out Steering pump, steering rack, ECU's, Suspension pump without any success. The problem (3 months later) turned out to be water in the conduit that runs front to back under the driver's seat. The drain from the sunroof had failed and the rain collected in the conduit, corroding the connectors in the conduit. The workshop (shout out to British Auto Solutions Katy, TX) cleaned the connectors and all was well. Great cars (I have four) but a royal PITA at times! Codes didn't help at all!