My intel is from the internet, so it must be correct.
The operational scenario, exaggerated, goes like this: If your driving style wears the pads into the first sensor wire by 1000 miles, the computer now knows Your wear rate and since the computer is programmed to know the remaining pad thickness it can then predict (shown on Nav) the remaining miles of life until the second sensor is reached... at which time the Lift lamp is thrown on the cluster. You can see the sensor topography supports this description and my picture of the old sensor shows that I had flattened all features on it. Yes the old style sensors simply completed the circuit and enabled a warning light. We could install new pads and reuse the sensor wire which would once again establish an open circuit until we wore down the pads to the sensor and completed the circuit again, a little later than a new sensor since we used some material. Now the sensors are smart and not merely analog electro mechanical devices. Someday the wear rate will be transmitted to the authorities and we will receive a fine for exhibiting 20th century road manners.
