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P0340 on MERCEDES-BENZ C-CLASS

Severity
Medium
NHTSA Reports
3
Most Affected
2013, 2012

What P0340 Means on Your MERCEDES-BENZ C-CLASS

Real MERCEDES-BENZ C-CLASS Owner Reports (Source: NHTSA Complaints Database)

"My check engine light came on while driving and i had it checked by a mechanic, the obc code was p0340 camshaft adjuster. my vehicle has less than 100,000 miles the camshaft adjuster should not need to be replace until around 250.000 miles."

— 2012 MERCEDES-BENZ C-CLASS owner • ENGINE • Filed 02/10/2020

"Check engine light code, p0340, camshaft position sensor. problem includes difficulty starting car, engine knock upon start, and misfires accelerating to pass at highway speeds."

— 2013 MERCEDES-BENZ C-CLASS owner • POWER TRAIN,ENGINE,FUEL/PROPULSION SYSTEM • Filed 08/15/2015

"My car has 47k mileage and the check engine light was on a few weeks ago. the error code was p0340 camshaft position sensor circuit malfunction. the mercedes benz dealer technicians checked the check and found that the issue was caused by timing chain and they had to replace it."

— 2013 MERCEDES-BENZ C-CLASS owner • ENGINE • Filed 04/09/2018

Data from NHTSA Vehicle Complaints Database. All reports are filed by vehicle owners directly with the U.S. Department of Transportation.

Common Causes of P0340 on MERCEDES-BENZ C-CLASS

66.7%
33.3%

Percentages based on NHTSA complaint component analysis for this vehicle.

Complaint Trend by Year

2012
1
2013
2

What To Do Next

  1. 1
    Check for recalls on YOUR VIN

    Go to nhtsa.gov/recalls and enter your VIN. Free repairs if your vehicle is covered.

  2. 2
    Get a proper diagnosis

    A code alone doesn't tell you the exact failed part. A diagnostic at a shop ($50-$150) pinpoints the root cause before you spend money on parts.

  3. 3
    Compare repair quotes

    Get 2-3 quotes. Dealer vs independent shop prices often differ 30-50% for the same repair.

P0340 on Other Vehicles

Data sourced from the National Highway Traffic Safety Administration (U.S. Department of Transportation) and the SAE J2012 OBD-II standard. Code definitions follow the SAE J2012 / ISO 15031-6 standard. Owner reports are filed directly with NHTSA by vehicle owners. This information is provided for educational purposes only and should not replace professional automotive diagnosis. Always consult a qualified mechanic for vehicle repair decisions.

Last updated: March 2026