rotor and brake pad

I never trust the warning lights for brake pad thickness. That system works very simple and can be faulty. Nothing replaces visual inspection. The problem with that system is it presents an opportunity to sell brakes when they are not worn out completely. As Pennsylvanians, we like to get the most out of everything , LOL. The minimum thickness for state safety inspection for PA is a pad thickness of 2/32ths of an inch. In my experience with LR and Mercedes is that system warns you at about 4/32ths. On the other hand, you've spoke nothing of your driving habits. If you brake hard and often, I have seen brakes last 20,000mi or LESS. Ultimately, get them inspected AND measured to see whats going on.