Home >> BMW >> 2012 >> 335xi Automatic Trans >> Repair and Diagnosis >> Engine Performance >> System >> Self Diagnosis - N55 - Diagnostic Trouble Codes - DTC P0478 (BMW DTC 138101) Through DTC P0440 (BMW DTC 191D01) >> DTC P13BE; BMW DTC 168A51: Knock sensor 2, electrical: signal input A, short circuit to ground >> Fault code