Mercedes-Benz C 300 2015–2025 — technical service bulletin

Bulletin LI01.20-P-076894 · NHTSA communication 11018530 · issued May 15, 2025

Technical service bulletin

communication type

Engine

component

2015–2025

model years

vehicle entries

Official summary

Complaint Check engine light illuminated Fault code stored in N3/10 control unit- P052E71 – Positive Crankcase Ventilation Regulator Valve Performance: The valve for crankcase ventilation has a malfunction Cause The partial-load ventilation valve (a part of the intake line assembly) may not work as intended. Remedy **Important** Replacement of the engine wiring harness or control unit is not needed if oil is found at the electrical connection of the crankcase ventilation valve or control unit. Replacement is only allowed if other symptoms or faults are present. Perform either remedy A or remed

Vehicles covered

What a TSB means. Technical service bulletins are repair guidance manufacturers send to dealers — they are not recalls, and repairs are not automatically free (warranty extensions are an exception worth checking). The full document is available via NHTSA’s vehicle lookup.