If you are searching for the , you are likely looking for the genuine OEM replacement part. While "4s0101" appears in some catalog listings, the primary BMW Part Number is 64119240180 .

: A faulty sensor can trigger "AUC Sensor" error codes when scanned with BMW diagnostic tools like ISTA or INPA.

: If you smell diesel or gasoline fumes inside your BMW M6 even when the AC is on, the sensor has likely failed.

: If the sensor fails in a way that keeps the car permanently in recirculation mode, excess moisture can cause the windows to fog up. Installation in the BMW M6

Over time, the chemical sensing element inside the AUC sensor becomes "poisoned" or worn out, losing its ability to distinguish between clean air and exhaust fumes.

In the BMW M6 E63/E64 (and related 5-series E60 models), the sensor is typically located on the or near the microfilter housing in the engine bay. This allows it to sample ambient air before it reaches the vehicle's intake vents. Installation is generally straightforward, requiring only a simple "plug-and-play" connection to the existing harness. BMW M6 Coupe E63 5.0L V10 AUC Sensor

: Often produced by HELLA (OEM) or directly as a genuine BMW part.

: It is typically a circular sensor weighing approximately 0.05 lbs . Why Replacement is Necessary