Home >> BMW >> 2011 >> X6 ActiveHybrid >> Repair and Diagnosis >> Engine Performance >> Testing & Diagnosis >> Diagnostic Trouble Codes (ACTIVEHYBRID) - DTC P0300, BMW DTC 140001 Through DTC P1408, BMW DTC 193108 >> DTC P033D, BMW DTC 168301: Knock-sensor signal 4, signal: engine noise above limit value >> Fault code