One problem related to traction control light on has been reported for the 2004 Land Rover Discovery Ii. The most recently reported issues are listed below.
Failure of abs system while driving. 3-4 times per week while city driving the abs/hill descent/traction control warning lights and chimes come on. The system typically resets after stopping and re-starting the vehicle (sometimes requires neutral start to reset). This is similar to a failure I had in a 1999 model that required over $3,000 in repairs to replace a failed abs pump. Land rover insists that there is no fault code left on the obc after these events, but all indications point to a systemic and on-going problem with the series of abs pumps used over the years. This seems to be an important safety system in the vehicle, but lr seems to have no interest in addressing it.