Before Hill Descent Control (HDC), slow and controlled descents in your Defender or Range Rover required some driver input. At the top of the hill, you selected first gear in low-range, then you headed down, without touching any of the pedals. You effectively used the engine as a brake. read more
Land Rover originally developed HDC for use on their Freelander model which lacks the low range gears usually provided on 4x4 vehicles. At the time it was derided by enthusiasts, and many claimed its set speed was too high for a controlled descent in difficult conditions. read more
When my wife starts the LR3 after it has been sitting for a while (cold) she says that the message center displays 'HDC Fault in System'. read more