Wheel speed sensor. Tire wore thru it. They wanted to charge me $250 to change a $26 part.
Charged mr $55 to diagnose. $26 sensor.
Pics coming when I get dirty doing it.
When the guy Said he had to take the rotor off, I stopped listening, and decided to do it myself.
A positive note was that after freaking out a little the dealer let me bring it in at 4:30pm.