2009 Mercedes Benz C300: check engine light

Filed Mar 12, 2026 · Electrical · 217,000 miles · AL

The contact owns a 2009 Mercedes-Benz C300. The contact stated that while starting the vehicle, the check engine, seat belt, and air bag warning lights illuminated. Additionally, the headlights and navigation lights failed to activate for a while. There was burning odor inside the vehicle with the heat activated or turned off. The contact also stated the vehicle failed to start for three days before eventually being able to start. The contact attempted to charge the battery, which resulted in a visible spark. The vehicle was taken to a dealer where it was diagnosed with a sound module and the Signal Acquisition Module (SAM) failures. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was 217,000.

Filed Jun 6, 2024 · Airbags, Engine · 99,000 miles · MS

The contact owns a 2009 Mercedes-Benz C300. The contact stated that while driving at an undisclosed speed, the "SRS System Requires Service" was displayed. The air bag and check engine warning lights were illuminated. The vehicle was taken to the dealer, who diagnosed a failure with the vapor canister shutoff valve but had not provided a diagnosis for the SRS system. The vehicle was repaired. The manufacturer was notified of the failure, and a case was opened. The failure mileage was 99,000.

Filed Sep 21, 2023 · Engine, Lights · LA

The contact owns a 2009 Mercedes-Benz C300. The contact stated while driving at an undisclosed speed, she became aware that the coolant level was low. The contact added coolant to the reservoir. The contact stated that the coolant reservoir burst open. The vehicle was towed to an independent mechanic who replaced the coolant and hose. The vehicle was taken to the local dealer but was not diagnosed or repaired. The vehicle was repaired, but the failure recurred. Additionally, the indicator lights became inoperable. The check engine warning light was illuminated. The contact stated the failure was associated with the federal safety agency Campaign Number: 22V168000 (Exterior Lighting, Electronic Stability Control, Engine and Engine Cooling). The manufacturer was contacted, but no assistance was provided. The failure mileage was unknown.

Filed Jul 27, 2021 · Body, Suspension · 120,000 miles · MO

The contact owns a 2009 Mercedes-Benz C300. The contact stated while driving approximately 60-70 mph, the vehicle started shuddering and lost stability. There were no warning lights illuminated. The contact stated that as she disengaged the accelerator pedal, the vehicle stopped shuddering. The vehicle was taken to an independent mechanic who diagnosed that the rear subframe was rusted and had fractured into two pieces on both sides of the vehicle, and the lower control arms were hitting the gas tank. The check engine warning light and TPMS warning light were illuminated at the time of the diagnosis. The manufacturer was not made aware of the failure. The vehicle was not repaired. The approximate failure mileage was 120,000.

Filed May 28, 2016 · Electrical, Steering · TX

When I've got to the car, put the key in the ignition, and turn the key with no crank noise in the engine. After a lot of tries I had noticed that my steering was not unlocking, windows don't work no lights on like ABS, check engine or all the lights that come on with the key on the on position, and that the car would not shift in neutral. After trying to jump the car and rearming/disarming the alarm I checked on line and found out that a lot of people have the same problem with their mercedes. Here is what I experienced 1.put key into ignition, steering wheel doesn't unlock. 2.instument cluster displays "remove key from ignition". 3.turn key to accessory, no lights on dashboard, only the radio works, windows don't work. 4.turn key all the way to start car, nothing happens.

Filed Feb 5, 2015 · Engine · 77,000 miles · GA

Tl* the contact owns a 2009 mercedes benz c300. While driving at various speeds, the vehicle shook and the check engine warning indicator illuminated. The failure recurred numerous times. The vehicle was taken to a dealer. The technician diagnosed that the spark plugs needed to be replaced. The vehicle was repaired, but the failure recurred. The manufacturer was not made aware of the failure. The failure mileage was 77,000.