P0340 on MERCEDES-BENZ C-CLASS
Camshaft Position Sensor A Circuit Bank 1 or Single Sensor
Methodology: Reviewed against the SAE J2012 generic DTC definition and NHTSA owner-complaint patterns, then scoped to Mercedes Benz C Class context without treating complaints as confirmed diagnoses.
Sources: SAE/OBD-II definitions, manufacturer service information, and public reliability reports (including NHTSA where applicable).
- SAE J2012 Diagnostic Trouble Code Definitions — Generic diagnostic trouble code definition reference for P0340.
- NHTSA recalls, complaints, and manufacturer communications — Used to check public owner complaint context, recall status, and safety-related manufacturer communications by VIN or vehicle.
Limits: Guidance is informational and may not match every model-year or revision. Confirm with the official manual and diagnostics before replacing parts. For safety-critical or electrical work, use a qualified technician.
What P0340 Means on Your MERCEDES-BENZ C-CLASS
P0340 is a diagnostic trouble code indicating: Camshaft Position Sensor A Circuit Bank 1 or Single Sensor. This code relates to the powertrain, fuel, ignition, emissions, or air-management system. The vehicle's computer detected a condition outside normal operating parameters and stored this code.
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."
"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."
"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."
All reports filed by vehicle owners directly with the U.S. Department of Transportation.
📊 Complaint Trend by Model Year
Common Causes on MERCEDES-BENZ C-CLASS
Based on NHTSA complaint component analysis for this vehicle.
What To Do Next
-
1
Check for recalls on YOUR VIN
Go to nhtsa.gov/recalls and enter your VIN. If your vehicle is covered, repairs are free.
-
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
Compare repair quotes
Get 2–3 quotes. Dealer vs. independent shop prices often differ 30–50% for the same repair.