Here are the dashboard warning lights and warning messages for the Mercedes-Benz C-Class. Both W204 model (2007–2014) and W205 model (2014–present) versions are covered. Dashboard instrument display layout and warning light location will vary depending on your model of C-Class. Warning lights not shown on the dashboard display are detailed towards the end of this page.
Mercedes-Benz C-Class speedometer.
Warning light name: Mercedes-Benz C-Class distance warning light.
Description: The Mercedes C-Class red triangle warning light comes on when the vehicle is in motion to warn the driver that the distance to the vehicle in front is too small for the speed selected. In addition, a warning alert may sound if you are approaching an obstacle at too high a speed. Be prepared to:
- Brake immediately.
- Increase the distance.
Warning light name: Mercedes-Benz C-Class power steering warning light.
Description: If the power steering warning light illuminates, steering function will be impaired. Significant effort may be required to steer the vehicle. Depending on your version of C-Class, the following messages may display:
- ‘Steering malfunction stop immediately‘. In this instance, total loss of steering assistance has occurred. It’s advised that you do not continue driving and consult with a Mercedes-Benz workshop.
- ‘Steering malfunction increased physical effort‘. Partial loss of steering assistance. If you are able to steer the vehicle, have it checked immediately.
Warning light name: Mercedes-Benz C-Class left / right indicators and hazard warning lights.
Mercedes-Benz C-Class multifunction information display.
Mercedes-Benz C-Class tachometer / rev counter.
Warning light name: Mercedes-Benz C-Class check engine warning light.
Description: The yellow check engine warning light illuminates indicating a malfunction in the engine, the exhaust system or the fuel system. In this situation, the engine may enter emergency mode. Emergency mode is a safety system which overrides normal use to reduce engine power. This helps to reduce the chances of failure. The check engine light comes on due to one or more of the following:
- the engine management
- the fuel injection system
- the exhaust system
- the ignition system
- the fuel system
You can usually continue driving, but have the vehicle checked as soon as possible. Diagnostic equipment is require to read fault codes.
Flashing check engine light
A flashing check engine light is usually a symptom of engine misfire. This is of greater seriousness as damage can occur due to excessive heat of fuel combustion. Immediately reduce speed and avoid high engine loads. Have vehicle checked immediately.
Warning light name: Mercedes-Benz C-Class diesel preheat / glow plugs warning light.
Description: The preheat / glow plugs light applies only to diesel versions of the C-Class. When the light goes out, the engine is ready to start. The light will remain on for longer in colder climates.
Warning light name: Mercedes-Benz C-Class PARK warning light (Red).
Description: The red PARK warning light is displayed as the in certain countries and illuminates indicating that the parking brake has been applied.
PARK warning light flashing
If the red PARK warning light is flashing, it’s an indication that the parking brake has not been fully released while driving. Attempt to release the parking brake manually by pulling the parking braking handle. If the red park warning light continues to flash, it indicates a malfunction. It’s advised that you do not continue to drive.
Warning light name: Mercedes-Benz C-Class BRAKE warning light (Red).
Description: The BRAKE warning light is also displayed as the symbol depending on your country. The brake warning light indicates the following:
- The brake force boosting is malfunctioning and the braking characteristics may be affected.
- There is insufficient brake fluid in the brake fluid reservoir.
Brake force boosting is a system that helps to increase brake force when the drivers depressed the brake pedal. If brake force boosting is malfunctioning. greater force may be required when pressing the brake pedal.
If the brake fluid is running low, it could be a symptom of a leak in the system which may severely reduce braking performance. It’s advised to stop the vehicle and consult with a Mercedes workshop before continuing.
Warning light name: Mercedes-Benz C-Class engine coolant warning light.
Description: If the red coolant warning light is lit while the engine is running, the possible causes are:
- The temperature sensor is malfunctioning
- The coolant level is too low
- The air supply to the radiator is obstructed
- The radiator fan is faulty
If there is an additional warning tone, the coolant temperature has exceeded the maximum permissible temperature.
- Pull off the road, stop the vehicle and switch off the engine.
- Allow the engine and coolant to cool.
- Check coolant level and add coolant if required. If the coolant level is correct, the airflow to the engine radiator may be blocked or the electric engine radiator fan may be malfunctioning. If you frequently need to add coolant, it’s likely there’s a leak in the system.
- Before continuing your journey, ensure the coolant light has gone out.
Mercedes-Benz C-Class engine coolant temperature gauge.
Warning light name: Mercedes-Benz C-Class PARK warning light (Yellow).
Description: The yellow PARK warning light is displayed as the in certain countries and illuminates indicating that the electric parking brake is malfunctioning. To apply or release the parking brake, switch off the ignition, switch it back on again and apply or release the parking brake manually by operating the handle. The electric parking brake may not operate if the vehicle battery is at low charge.
Warning light name: Mercedes-Benz C-Class ABS warning light.
Description: The ABS (anti-lock braking system) is responsible for preventing the wheels locking during emergency braking. If the yellow ABS warning lamp is lit while the engine is running, ABS is malfunctioning. If there is an additional warning tone, EBD (electronic brakeforce distribution) is malfunctioning. EBD applies varied brake pressure on individual wheels to help improve braking performance. You can continue driving, but avoid harsh braking if possible and have your vehicle checked as soon as possible.
Warning light name: Mercedes-Benz C-Class airbag warning light.
Description: If the red airbag / restraint system warning light is lit while the engine is running, the restraint system is malfunctioning. Restraint system components may be triggered unintentionally or might not be triggered at all in the event of an accident. This may affect the Emergency Tensioning Device / Supplemental Restraint System (SRS) or airbag. Drive carefully and have system checked as soon as possible.
Warning light name: Mercedes-Benz C-Class seat belt warning light.
Description: Seat belt not fastened. The warning light goes out when seat belts are fastened.
Warning light name: Mercedes-Benz C-Class high beam warning light.
Description: This blue warning light illuminates when high beam / main beam is activated.
Warning light name: Mercedes-Benz C-Class low beam warning light.
Description: This green warning light illuminates when low beam is activated.
Warning light name: Mercedes-Benz C-Class fuel reserve warning light.
Description: The yellow fuel reserve warning lamp lights up while driving for the following reasons:
- The fuel supply has dropped into the reserve range and the vehicle requires refueling.
- The fuel filler cap is not closed correctly. If the remaining fuel levels becomes too low, the check engine warning light may illuminate. Check that the fuel cap is closed properly. If it is properly closed and the warning light remains on, contact a Mercedes workshop.
- There has been pressure loss in the fuel system.
- The fuel system is leaking.
The arrow to the side of the fuel symbol indicates which side of the filler flap is located.
Mercedes-Benz C-Class fuel level gauge.
Mercedes-Benz C-Class parking lights warning symbol.
Mercedes-Benz C-Class rear fog lights warning symbol.
Warning light name: Mercedes-Benz C-Class low tyre pressure warning light.
Description: The yellow tyre pressure monitoring system (TPMS) warning light illuminates for the following reasons:
- The tyre pressure monitoring system has detected pressure loss in at least one of the tyres. Carefully pull off the road avoid harsh braking or steering movements. Stop the car and check tyre pressures or replace wheel with spare. See Mercedes C-Class tyre pressure reset for a guide on how to reset the tyre pressure monitoring system.
Low tyre pressures
Tyre pressures that are too low pose the following hazards:
- Tyres at risk of bursting, especially as the load and vehicle speed increase.
- Tyres may wear excessively and/or unevenly, which may greatly impair vehicle stability.
- The driving characteristics, as well as steering and braking, may be greatly impaired, resulting in loss of control of the vehicle.
The yellow tyre pressure monitoring system warning light flashes for approximately one minute and then remains lit. This indicates that the tyre pressure monitoring system is defective.
Warning light name: Mercedes-Benz C-Class low ESP OFF warning light.
Description: ESP ( (Electronic Stability Program) has been switched off or automatically deactivated. It’s generally safer to keep ESP switched on at all times, however, if your vehicle becomes stuck in snow or mud, turning off ESP / traction control can prove beneficial for getting the vehicle unstuck.
Warning light name: Mercedes-Benz C-Class low ESP warning light.
Description: ESP ( (Electronic Stability Program) is a combination of vehicle stability systems that help to maintain safety and stability. There are certain modes available that limit how much ESP intervenes, or there’s the option to switch it off. ESP is on by default each time the vehicle is started.
Additional Mercedes C-Class Dashboard Warning Lights
These are additional Mercedes warning lights not detailed on the diagram above.
Warning light name: Mercedes-Benz C-Class EBD/ABS/ESP warning lights.
Description: The stability systems EBD/ABS/ESP have malfunctioned.
- EBD (electronic brakeforce distribution) is responsible for distributing safe limits of braking force on individual wheels.
- ABS (anti-lock braking system) is responsible for preventing the wheels from locking during emergency braking.
- ESP (Electronic Stability Program) is a combination of vehicle stability system.
Note: Vehicle can be driven carefully. Vehicle may be prone to instability. EBD and ESP rely on ABS sensors to operate. Have vehicle checked as soon as possible.
Warning light name: Mercedes-Benz C-Class battery warning light.
Description: If the red battery warning light comes on while driving, it means the battery is no longer being charged. Action required depends on the message displayed on the instrument cluster:
- If only the battery warning light illuminates, or the ‘Stop Vehicle‘ message is displayed, it’s recommended that you safely stop the vehicle and switch off the engine. Engine cooling may be interrupted and engine damage may occur. Consult Mercedes workshop and do not continue driving.
- Message: ‘Stop Vehicle Leave Engine Running‘ – In this instance, the battery charge is low. Safely pull off the road, stop the vehicle and leave the engine running until the message goes off.
- Charging faults: Faults related to the battery are often the alternator, serpentine belt. the battery or electrical / wiring issue.
Warning light name: Mercedes-Benz C-Class oil sensor warning light.
Description: The following message may be displayed: ‘Engine Oil Level Cannot Be Measured‘. This is due to the electrical connection to the oil level sensor being interrupted or the oil level sensor is faulty.
Warning light name: Mercedes-Benz C-Class oil level warning light.
Description: This red oil level warning light will usually illuminate when the oil level is getting low and requires topping up as soon as possible. If a message appears indicating that the oil level or oil pressure is low and instructing you to stop and switch off the engine, it’s essential that this is done immediately to avoid severe engine damage. Very low oil levels or oil pressure interrupts the lubrication system and will damage engine components. This is usually not covered by warranty.
Warning light name: Mercedes-Benz C-Class SmartKey warning light.
Description: The Mercedes-Benz C-Class SmartKey warning message ‘Key Not Detected‘ may illuminate in red or white. In this instance you may not be able to start the engine or lock the vehicle. Try the following:
- Ensure that the SmartKey is in the vehicle.
- Change the location of the SmartKey in the vehicle.
- Check to ensure the battery in the SmartKey doesn’t require replacing. See Mercedes C-Class key battery change for details on how to do this and the type of batteries required.
- If you are still unable to start the vehicle, place the SmartKey in the SmartKey slot.
- Ensure the SmartKey slot area is empty (2).
- Remove key ring from the SmartKey.
- Place the SmartKey in the slot (2) and onto the symbol (3).
- The vehicle will start after a short time.
Warning light name: Mercedes-Benz C-Class vehicle lights fault warning light.
Description: The light bulb containing an exclamation mark is an indication that a fault has occurred with the vehicle lights or that they need to be switched on or off. A message will explain details further.
Warning light name: Mercedes-Benz C-Class brake pads warning light.
Description: The brake pads warning light illuminates indicating that they are wearing low and require changing. There is approximately 1000 miles (1600 km) remaining of pad wear left though this is dependent on how the vehicle is driven.
Warning light name: Mercedes-Benz C-Class low coolant warning light.
Description: This warning light indicates that the engine coolant is too low. This is not a critical warning, but coolant should be added at your next stop and before a long journey.
Warning light name: Mercedes-Benz C-Class ECO start stop warning light.
Description: The green ECO engine start stop warning light illuminates when the engine has been stopped by the system (auto-stop). A yellow symbol or ECO symbol will illuminate if the system is not ready or specific conditions have not been met for auto-stop to take place. See Mercedes C-Class start stop not working for the possible conditions that must be met.