Home >> BMW >> 2012 >> X5 35i >> Repair and Diagnosis >> Engine Performance >> System >> Self Diagnosis - N55 - Diagnostic Trouble Codes - DTC P10C9 (BMW DTC 10BA42) Through DTC P0001 (BMW DTC 11C404) >> DTC P0171; BMW DTC 118401: System Too Lean (Bank 1) >> Fault code