Home >> BMW >> 2013 >> 135is 2D Convertible, Automatic DCT Trans >> Repair and Diagnosis >> Engine Performance >> System >> Self Diagnosis - N55 - Diagnostic Trouble Codes - DTC P0234 (BMW DTC 120208) Through DTC P10F6 (BMW DTC 135B12) >> DTC P12DB; BMW DTC 121533: Boost pressure sensor, plausibility: Pressure before throttle valve too low when engine not running >> Fault code