What is the Mercedes Crank Position Sensor?

The crank position sensor is the sensor that measures TDC or top dead center of the crankshaft. Its located on the bell housing of the transmission and is a magnet type sensor and measures a toothed ring on the flywheel, can be access ususlly from the top of the engine at the rear/drivers side. they def. go bad and can cause crank/no start complaints......especially when hot!