P0340 on MERCEDES-BENZ C-CLASS — Camshaft Position Sensor A Circuit Bank 1 or Single Sensor

Q: "What does P0340 mean on a MERCEDES-BENZ C-CLASS?"

"P0340 indicates: Camshaft Position Sensor A Circuit Bank 1 or Single Sensor. This is a ignition system code. 3 MERCEDES-BENZ C-CLASS owners have reported this to NHTSA."

Q: "What are the most common causes of P0340 on MERCEDES-BENZ C-CLASS?"

"Based on 3 NHTSA reports, the most commonly cited components are: Engine, Power Train,Engine,Fuel/Propulsion System. These percentages are based on the component field in owner complaints."

Q: "Is P0340 serious on my MERCEDES-BENZ C-CLASS?"

"Of 3 NHTSA reports for this code on MERCEDES-BENZ C-CLASS, none involved a crash or fire. However, any diagnostic code should be evaluated by a qualified mechanic."

Q: "What should I do if my MERCEDES-BENZ C-CLASS shows P0340?"

"1) Check for recalls on your VIN at nhtsa.gov/recalls. 2) Get a professional diagnosis — a code alone doesn't identify the exact failed part. 3) Get 2-3 repair estimates to compare."

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 ignition system system. The vehicle's computer detected a condition outside normal operating parameters and stored this code.

3 MERCEDES-BENZ C-CLASS owners have reported this issue to NHTSA across model years 2012-2013. Most reports come from the 2013, 2012 model years. The most commonly reported component is Engine (66.7% of reports).

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

All reports filed by vehicle owners directly with the U.S. Department of Transportation.

📊 Complaint Trend by Model Year

1

'12

2

'13

Common Causes on MERCEDES-BENZ C-CLASS

Based on NHTSA complaint component analysis for this vehicle.

ENGINE 66.7%

POWER TRAIN,ENGINE,FUEL/PROPULSION SYSTEM 33.3%

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.

Frequently Asked Questions

What does P0340 mean on a MERCEDES-BENZ C-CLASS? ▾

P0340 indicates: Camshaft Position Sensor A Circuit Bank 1 or Single Sensor. This is a ignition system code. 3 MERCEDES-BENZ C-CLASS owners have reported this to NHTSA.

What are the most common causes of P0340 on MERCEDES-BENZ C-CLASS? ▾

Based on 3 NHTSA reports, the most commonly cited components are: Engine, Power Train,Engine,Fuel/Propulsion System. These percentages are based on the component field in owner complaints.

Is P0340 serious on my MERCEDES-BENZ C-CLASS? ▾

Of 3 NHTSA reports for this code on MERCEDES-BENZ C-CLASS, none involved a crash or fire. However, any diagnostic code should be evaluated by a qualified mechanic.

What should I do if my MERCEDES-BENZ C-CLASS shows P0340? ▾

1) Check for recalls on your VIN at nhtsa.gov/recalls. 2) Get a professional diagnosis — a code alone doesn't identify the exact failed part. 3) Get 2-3 repair estimates to compare.