Let me clarify the brake sensor system on this car. It has two stages.
The first stage is the computer estimates when you should replace the brake pads based on the computer algorithm ( I don't know how it does it). It tells you to get a brake service within a certain mile. That one is not good at all and often way off.
The second stage is when the pads get worn down to about 2 mm and it will trip the brake sensors. This one will give you an emergency alert on your screen to replace your pads immediately and 0 mile left. This one is accurate.
I guess if I were the engineer for the brake sensor and wanted two stages, then I would design the sensor at 4 mm thick or something along that line. The first stage will be tripped at 4 mm and the second stage would trip at 2 mm. That way it will be accurate but I'm sure it will cost much more and people wont' pay for it
. I'm rambling now.