My 1999 Disco II has the ABS, TDC and TC lamps illuminate at the same time. The lamps all three come on at the same time and will remain on for awhile and then go back out. The lamps will light everytime you stand on the brakes really hard. I do not notice any difference in the braking when the lamps are on. While the problem existed when I purchased the car, I have had the brakes replaced since and it did not correct the problem.

Should I be overly concerned? Is there any suggestions as to what I can look at to eleviate this issue?

 

Do a search for the "3 amigos". This is a known and very common issue with the D2's.

 

The three amigos come on when there is a fault in either the traction control or ABS systems (they are linked and hence all of the lights come on when there is a fault in one system). Changing the brakes (ie the pads and/or rotors) will not correct any problem, if there is one, because the electronics of the system are separate from the mechanical end. The lights could be coming on like you said as a result of a ABS speed sensor retrieving a bad signal. That means the sensor could be dirty or broken. Regardless, the only way to pinpoint what is going on is to go to either the dealer (expensive) or a local mechanic that has a laptop scanner which can read Land Rover ABS codes and see whats going on. I wouldnt be too concerned until the lights come on indefinately but thats just my opinion.

As for having the brakes feel the same........... they will function completely as normal but without the ABS or Traction control systems. When the lights are on these systems are shut off.

 

You can try this. Doing a hard brake on loose gravel to find out if the brake pedal pulses, indicating that the ABS is working.