Mercedes-Benz A-CLASS SEDAN 2021 Warning and Indicator Lights User Manual
Welcome to the Mercedes-Benz A-Class Sedan 2021 world, where luxury and innovation converge. We will dig into the variety of warning and indication lights that decorate this smart vehicle’s dashboard in this introductory tutorial. It’s important to become familiar with the numerous lights that act as your car’s talking partners before you set out on your adventure with the A-Class Sedan. These lights, which are intended to keep you informed and safe, act as an essential conduit between you and the complex systems in your automobile. Each light has a distinct function, from vital alerts that require immediate attention to educational signs that direct you while driving every day. These lights are one of several cutting-edge technologies that the A-Class Sedan is outfitted with, and they are essential to ensure that it performs at its best. We’ll explain each symbol and its meaning in this guide so you can understand the information they’re trying to communicate. Understanding these warning and indication lights enables you to take the proper measures and keep your A-Class Sedan in top shape, whether it’s a signal regarding engine health, tire pressure, or active safety features. Come along on this educational tour of the Mercedes-Benz A-Class Sedan 2021’s warning and indication lights as you obtain the assurance to face any adventure with calm.
Display messages
Information about display messages
Display messages appear on the multifunction display. Display messages with graphical symbols are simplified in the Operator’s Manual and may differ from the symbols on the multifunction display. The multifunction display shows high-priority display messages in red. Certain display messages are accompanied by a warning tone.
Please act in accordance with the display messages and follow the additional notes in the Operator’s Manual.
For some display messages, a symbol will also be shown:
Further information
Hide display message
With the left-hand Touch Control, you can select the respective symbol by swiping to the left or right. Press thesymbol to show further information on the media display. Press the¨ symbol to hide the display message. You can hide low-priority display messages by pressing the back button or the left-hand Touch Control. The display messages will then be stored in the message memory.
Rectify the cause of a display message as quickly as possible. High-priority display messages cannot be hidden. The multifunction display shows these display messages continuously until the cause of the display message has been rectified.
Calling up saved display messages
On-board computer:
If there are no display messages, No Messages will appear on the multifunction display.
- Scroll through the display messages by swiping upwards or downwards on the left-hand Touch Control.
- To exit the message memory: press the back button
.
Occupant safety
| Display messages | Possible causes/consequences and M Solutions | ||
|
SRS Malfunction Service Required |
* The restraint system is malfunctioning (/ page 37). | ||
| & WARNING Risk of injury due to malfunctions in the restraint system | |||
| Components in the restraint system may be activated unintentionally or not deploy as planned in an accident. # Have the restraint system checked and repaired immediately at a qualified specialist workshop. |
|||
|
Front Left Malfunction Service Required (example) |
* The corresponding restraint system is malfunctioning . | ||
| & WARNING Risk of injury due to malfunctions in the restraint system | |||
| Components in the restraint system may be activated unintentionally or not deploy as planned in an accident. # Have the restraint system checked and repaired immediately at a qualified specialist workshop. |
|||
|
Left Side Curtain Airbag Malfunction Service Required (example) |
* The corresponding window curtain airbag is malfunctioning (/ page 37). | ||
| & WARNING Risk of injury or fatal injury due to a malfunction in the window curtain airbag | |||
| The window curtain airbag might be triggered unintentionally or might not be triggered at all in the event of an accident. # Have the window curtain airbag checked and repaired immediately at a qualified specialist workshop. |
|||
| Display messages | Possible causes/consequences and M Solutions |
|
Front Passenger Airbag Dis- abled See Operator’s Man- ual |
* The front passenger airbag and the front passenger knee airbag have been disabled even though an adult or a per‐ son of adult stature is on the front passenger seat. If additional forces are applied to the seat, the weight the sys‐ tem detects may be too low.
& WARNING Risk of injury or fatal injury due to a disabled front passenger airbag If the front passenger airbag is disabled, the front passenger airbag will not be deployed in the event of an acci‐ dent and cannot perform its intended protective function. A person in the front passenger seat could then, for example, come into contact with the vehicle’s interior, especially if the person is sitting too close to the cockpit. # Make sure, both before and during the journey, that the status of the front passenger airbag is correct. |
| Front Passenger Airbag Enabled See Operator’s Manual | * The front passenger airbag and the front passenger knee airbag will be enabled while the vehicle is in motion in the following situations:
R Even when a child, a small adult or an object weighing less than the system weight threshold is located on the front passenger seat |
| Display messages | Possible causes/consequences and M Solutions |
| The system may detect objects or forces that are adding to the weight applied to the seat.
& WARNING Risk of injury or death when using a child restraint system while the front passenger airbag is enabled The child could be struck by the airbag. |
|
| PRE-SAFE Inoperative See Operator’s Manual | * The PRE‑SAFE® functions are malfunctioning. # Consult a qualified specialist workshop. |
SmartKey
| Display messages | Possible causes/consequences and M Solutions |
|
|
* Have SmartKey replaced. # Consult a qualified specialist workshop. |
Replace Key Battery |
* The SmartKey battery is discharged. # Replace the battery (/ page 68). |
|
Key Not Detected (white display message) |
* The SmartKey is currently undetected. # Change the location of the SmartKey in the vehicle. # If the SmartKey is still not recognized, place it in the marked space for starting with the SmartKey (/ page 127). |
| Display messages | Possible causes/consequences and M Solutions |
|
Key Not Detected (red dis‐ play message) |
* The SmartKey cannot be detected and may no longer be in the vehicle. The SmartKey is no longer in the vehicle and you switch off the engine: R You can no longer start the engine. R You cannot centrally lock the vehicle. # Ensure that the SmartKey is in the vehicle.If the SmartKey detection function has a malfunction due to a strong radio signal source:
# Stop the vehicle immediately in accordance with the traffic conditions. |
|
Don’t Forget Your Key |
* A warning tone also sounds. This message reminds you to take your SmartKey with you when you leave the vehicle. |
| Place the Key in the Marked Space See Opera- tor’s Manual | * SmartKey detection is malfunctioning.
# Change the location of the SmartKey in the vehicle. # Place the SmartKey in the marked space for starting the engine with the SmartKey (/ page 127). |
Lights
| Display messages | Possible causes/consequences and M Solutions |
Check Left Low Beam (example) |
* The corresponding light source is faulty. # Drive on carefully. # Consult a qualified specialist workshop immediately. % LED light sources: the display message for the corresponding light appears only when all the light-emitting diodes in the light are faulty. |
| Malfunction See Opera- tor’s Manual |
* The exterior lighting is malfunctioning. # Consult a qualified specialist workshop. |
|
Automatic Headlamp Mode Inoperative |
* The light sensor is malfunctioning. # Consult a qualified specialist workshop. |
| Display messages | Possible causes/consequences and M Solutions |
|
Active Headlamps Inopera- tive |
* The active headlamps are malfunctioning. # Consult a qualified specialist workshop. |
|
Switch On Headlamps |
* You are driving without low-beam headlamps. # Turn the light switch to the L or à position. |
|
Switch Off Lights |
* You are leaving the vehicle and the lights are still switched on. # Turn the light switch to the à position. |
|
Intell. Light System Inoper- ative |
* The Intelligent Light System is malfunctioning. The lighting system continues to function properly without the func‐ tions of the Intelligent Light System. # Consult a qualified specialist workshop. |
| Display messages | Possible causes/consequences and M Solutions |
| Adaptive Highbeam Assist Currently Unavailable See Operator’s Manual | * Adaptive Highbeam Assist is temporarily unavailable. The system limits have been reached (/ page 112).
Once the cause of the problem is no longer present, the system will be available again. The Adaptive Highbeam Assist Now Available display message will appear. |
| Adaptive Highbeam Assist Inoperative | * Adaptive Highbeam Assist is malfunctioning. # Consult a qualified specialist workshop. |
| Hazard Warning Flashers Malfunctioning | * The hazard warning lamp switch is malfunctioning. # Consult a qualified specialist workshop. |
Vehicle
| Display messages | Possible causes/consequences and M Solutions | ||
 |
* You are leaving the vehicle when it is in a ready-to-drive state.
# When you leave the vehicle, switch off the ignition, secure the vehicle against rolling away and take the Smart‐ Key with you. # If you do not leave the vehicle, switch off the electrical consumers, e.g. the seat heating. Otherwise, the 12 V battery may discharge and it will then be possible to start the vehicle only with the aid of a second battery (starting assistance). |
||
| Vehicle Ready to Drive Switch the Ignition Off Before Exiting | |||
|
Steering Malfunction Increased Physical Effort See Operator’s Manual |
* The power steering assistance is malfunctioning. | ||
| & WARNING Risk of an accident due to altered steering characteristics | |||
| If the power assistance of the steering fails partially or completely, you will need to use more force to steer. # If safe steering is possible, drive on carefully. # Visit or consult a qualified specialist workshop immediately. |
|||
 |
* The steering is malfunctioning. Steering capability is significantly impaired.
& WARNING Risk of accident if steering capability is impaired |
||
| Steering Malfunction Stop | |||
| Immediately See Operator’s Manual | |||
| Display messages | Possible causes/consequences and M Solutions | ||
|
|
# Pull over and stop the vehicle safely as soon as possible, paying attention to road and traffic conditions.
Do not continue driving under any circumstances. |
||
|
Steering Malfunction See Operator’s Manual |
* The electric steering lock is malfunctioning. The steering may be locked by the electric steering lock. WARNING Risk of accident if steering capability is impairedIf the steering does not function as intended, the vehicle’s operating safety is jeopardized. # Pull over and stop the vehicle safely as soon as possible, paying attention to road and traffic conditions.
Do not continue driving under any circumstances. # Consult a qualified specialist workshop. |
||
|
Before Starting the Engine, Turn Steering Wheel |
* The electric steering lock could not unlock the steering.
# Switch off the ignition. |
||
| Display messages | Possible causes/consequences and M Solutions |
|
|
* At least one door is open. # Close all doors. |
|
|
* The hood is open. & WARNING Risk of accident due to driving with the hood unlocked The hood may open and block your view.# Never release the hood when driving. # Before every trip, ensure that the hood is locked. # Stop the vehicle immediately, paying attention to road and traffic conditions. # Close the hood. |
|
|
* The trunk lid is open. & DANGER Risk of exhaust gas poisoning Combustion engines emit poisonous exhaust gases such as carbon monoxide. Exhaust gases can enter the vehicle interior if the trunk lid is open when the engine is running, especially if the vehicle is in motion.# Always switch off the engine before opening the trunk lid. # Never drive with the trunk lid open. |
| Display messages | Possible causes/consequences and M Solutions |
| # Close the trunk lid. | |
 Check Washer Fluid |
* The washer fluid level in the washer fluid reservoir has dropped below the minimum. # Add washer fluid (/ page 256). |
|
Engine |
|
| Display messages | Possible causes/consequences and M Solutions |
| To switch engine off, press and hold Start/Stop but- ton for at least 3 seconds or press 3 times. | * You have pressed the start/stop button while the vehicle is in motion.
# Information about switching off the engine while driving (/ page 126). |
Check Coolant Level See Operator’s Manual |
* The coolant level is too low. * NOTE Engine damage due to insufficient coolant # Avoid long journeys with insufficient coolant. # Add coolant (/ page 255). |
| Display messages | Possible causes/consequences and M Solutions |
| # Have the engine cooling system checked at a qualified specialist workshop. | |
|
Coolant Too Hot Stop Vehi- cle Turn Engine Off |
* The coolant is too hot. Pull over and stop the vehicle safely and switch off the engine, paying attention to road and traffic conditions.# Wait until the engine has cooled down. # Make sure that the air supply to the radiator is not obstructed. # Avoiding high loads on the engine, drive to the nearest qualified specialist workshop. In doing so, ensure that the coolant temperature display remains below the red marking. |
|
|
* The fan motor is faulty. # Avoiding high loads on the engine, drive to the nearest qualified specialist workshop. In doing so, ensure that the coolant temperature display remains below the red marking. |
| Display messages | Possible causes/consequences and M Solutions |
Fuel Level Low |
* The fuel supply has dropped into the reserve range. # Refuel. |
|
|
* The fuel filler cap is not closed correctly or the fuel system is leaking. # Close the fuel filler cap. # If the fuel filler cap was already properly closed: consult a qualified specialist workshop. |
|
Transmission |
|
| Display messages | Possible causes/consequences and M Solutions |
| Only Shift to ‘P’ when Vehi- cle is Stationary | * It is possible to select the park position j only if the vehicle is stationary.
# To stop, depress the brake pedal. # Shift the transmission to park position j when the vehicle is stationary. |
| Apply Brake to Shift from ‘P’ | * You have attempted to shift the transmission out of park position j and into another transmission position.
# Depress the brake pedal. # Select transmission position h, k or neutral i. |
| Display messages Possible causes/consequences and M Solutions | |
| To Deselect P or N, Depress Brake and Start Engine | * You have attempted to shift the transmission out of park position j or neutral i and into another transmission position.
# Depress the brake pedal. # Start the engine. # Change the transmission position. |
| Apply Brake to Shift to D or R | * You have attempted to select transmission position h or k.
# Depress the brake pedal. # Select transmission position h or k. |
| Apply Brake to Shift to ‘R’ | * You have attempted to select transmission position k.
# Depress the brake pedal. # Select transmission position k. |
| Driver’s Door Open & Transmission Not in P Risk of Vehicle Rolling Away | * The driver’s door is not fully closed and transmission position h, k or neutral i is selected.
# Select park position j when switching off the vehicle. |
| N Permanently Active Risk of Rolling Away | * While the vehicle is rolling or while you are driving, neutral i has been engaged.
# To stop, depress the brake pedal. # Shift the transmission to park position j while the vehicle is stationary. # To continue driving, select transmission position h or k. |
| Display messages Possible causes/consequences and M Solutions | |
| Service Required Do Not Shift Gears Visit Dealer | * The transmission is malfunctioning. The transmission position can no longer be changed.
# When transmission position h is selected, consult a qualified specialist workshop and do not change the trans‐ mission position. # For all other transmission positions, park the vehicle safely. # Consult a qualified specialist workshop or breakdown service. |
| Reversing Not Possible Service Required | * The transmission is malfunctioning. The transmission position k cannot be selected.
# Consult a qualified specialist workshop. |
| Transmission Malfunction Stop | * The transmission is malfunctioning. The transmission shifts to neutral i automatically.
# Stop the vehicle immediately in accordance with the traffic conditions. # Depress the brake pedal. # Engage park position j. # Consult a qualified specialist workshop. |
| Transmission Malfunction | * The transmission is malfunctioning. The cause could be an overheated clutch or blocked gears.
# Let the transmission cool down. # If the display message still appears following a restart, consult a qualified specialist workshop. |
| Display messages Possible causes/consequences and M Solutions | |
Transmission Oil Overhea- ted Drive with Caution |
* The transmission is overheating. When the display message is active, start-up and driving characteristics may be temporarily impaired. # Drive at low engine speed. # Avoid sporty driving. # Before pulling away on uphill gradients, let the transmission cool down until the display message disappears. |
| Parking Lock Inoperative Apply Parking Brake | * The transmission is malfunctioning. The park position j cannot be selected.
# Park the vehicle safely. # Use the electric parking brake to secure the vehicle against rolling away. |
| Teaching in Transmission Operate Selector Lever Apply Brake for XX s Risk of Vehicle Rolling Away | * The transmission is being taught in. There is a risk of the vehicle rolling away.
# Depress and hold the brake pedal until the teach-in process has been completed. The electric parking brake is applied automatically during the teach-in process. # Switch on the ignition. # Select park position j, transmission position k or neutral i. |
| Apply Parking Brake Risk of Rolling Away See Opera- tor’s Manual | * The transmission position cannot be reliably identified.
# Use the electric parking brake to secure the vehicle against rolling away. |
| Teaching in Transmission Complete | * The transmission’s teach-in process is complete. All transmission positions can be selected again. |
| Display messages | Possible causes/consequences and M Solutions |
| Transmission Malfunction Service Required | * The transmission is malfunctioning.
Consult a qualified specialist workshop. |
| Auxiliary Battery Malfunc- tion | * The auxiliary battery for the transmission is no longer being charged.
# Consult a qualified specialist workshop. # Until then, always select park position j manually before you switch off the engine. # Before leaving the vehicle, apply the electric parking brake. |
Brakes
| Display messages | Possible causes/consequences and M Solutions |
 |
* The yellow  indicator lamp is lit. The electric parking brake is malfunctioning.
To apply: # Switch the ignition off and switch it back on. If it is not possible to apply the electric parking brake: # Consult a qualified specialist workshop. To release: # Switch the ignition off and switch it back on. # Do not continue driving. Consult a qualified specialist workshop. |
| (USA only) | |
|
|
| (Canada only) | |
| Parking Brake See Opera- tor’s Manual |
| Display messages Possible causes/consequences and M Solutions | |
| * The yellow indicator lamp is lit and the red (USA only) or (Canada only) indicator lamp is flashing. The electric parking brake is malfunctioning.
The electric parking brake could not be applied or released. # Switch the ignition off and switch it back on. To apply: # Release and then apply the electric parking brake manually (/ page 149). To release: # Apply and then release the electric parking brake manually. If the electric parking brake cannot be applied or the red # Do not continue driving. Consult a qualified specialist workshop. # Where necessary, also secure the parked vehicle against rolling away. * The yellow If the charge level is too low: # Charge the 12 V battery. |
|
| Display messages Possible causes/consequences and M Solutions | |
| To apply:
# Switch the ignition off. The electric parking brake will be applied automatically. If you do not want the electric parking brake to be applied, e.g. at an automatic car wash or when the vehicle is being towed, leave the ignition switched on. This does not include having the vehicle towed with the rear axle raised. If the electric parking brake is not applied automatically: # Switch the ignition off and switch it back on. # Release and then apply the electric parking brake manually (/ page 149). If it is still not possible to apply the electric parking brake: # Consult a qualified specialist workshop. # Where necessary, also secure the parked vehicle against rolling away. To release: # If the conditions for automatic release are fulfilled and the electric parking brake is not released automatically, release the electric parking brake manually (/ page 149). If it is still not possible to release the electric parking brake: # Do not continue driving. Consult a qualified specialist workshop. |
|
| Display messages | Possible causes/consequences and M Solutions |
|
(USA only)
|
* The red indicator lamp (USA only) or indicator lamp (Canada only) is flashing. The electric parking brake is applied while you are driving:
R A condition for automatic release of the electric parking brake has not been fulfilled (/ page 149). # Check the conditions for automatic release of the electric parking brake. |
| (Canada only) | |
| Please Release Parking | |
| Brake |
| Display messages | Possible causes/consequences and M Solutions |
|
* The red (USA only) or indicator lamp (Canada only) is lit.
You have attempted to release the electric parking brake with the ignition switched off. # Switch on the ignition. |
| (USA only) | |
|
|
| (Canada only) | |
| Turn On the Ignition to | |
| Release the Parking Brake | |
 |
* There is insufficient brake fluid in the brake fluid reservoir.
& WARNING Risk of an accident due to low brake fluid level If the brake fluid level is too low, the braking effect and the braking characteristics may be impaired. Do not continue driving under any circumstances. |
| (USA only) | |
 |
|
| (Canada only) | |
| Check Brake Fluid Level |
| Display messages | Possible causes/consequences and M Solutions |
| Check Brake Pads See Operator’s Manual | * The brakepads have reached the wear limit. # Consult a qualified specialist workshop. |
|
Driving systems |
|
| Display messages | Possible causes/consequences and M Solutions |
 Off |
* The HOLD function is deactivated because the vehicle is slipping or a condition for activation is not fulfilled. # Reactivate the HOLD function later or check the activation conditions for the HOLD function. |
 ATTENTION ASSIST Inoperative |
* ATTENTION ASSIST is malfunctioning. # Consult a qualified specialist workshop. |
| Display messages Possible causes/consequences and M Solutions | |
|
ATTENTION ASSIST: Take a Break! |
* ATTENTION ASSIST has detected fatigue or an increasing lack of concentration on the part of the driver. # If necessary, take a break. |
 – – – mph |
* Cruise control cannot be activated as not all activation conditions are fulfilled. # Observe the activation conditions for cruise control (/ page 161). |
| Cruise Control Inoperative | * Cruise control is malfunctioning. # Consult a qualified specialist workshop. |
| Cruise Control Off | * Cruise control has been deactivated. If there is an additional warning tone, cruise control has been deactivated automatically . |
 – – – mph |
* Active Distance Assist DISTRONIC cannot be activated as not all activation conditions are fulfilled. # Comply with the activation conditions of Active Distance Assist DISTRONIC. |
| Display messages Possible causes/consequences and M Solutions | |
| Suspended |
* If you depress the accelerator pedal beyond the Active Distance Assist DISTRONIC setting, the system will switch to passive mode. |
| Off |
* Active Distance Assist DISTRONIC was deactivated. If a warning tone also sounds, Active Distance Assist DISTRONIC has deactivated automatically. |
| Active Distance Assist Currently Unavailable See Operator’s Manual | * Active Distance Assist DISTRONIC is temporarily unavailable. The ambient conditions are outside the system limits. As soon as the ambient conditions are within the system limits, the system will become available again. # Drive on. |
| Active Distance Assist Inoperative | * Active Distance Assist DISTRONIC is malfunctioning. Other driving systems and driving safety systems may also be malfunctioning. # Consult a qualified specialist workshop. |
| Active Distance Assist Now Available | * Active Distance Assist DISTRONIC is operational again. # Switch on Active Distance Assist DISTRONIC (/ page 164). |
| Display messages Possible causes/consequences and M Solutions | |
| Active Steering Assist Cur- rently Unavailable See Operator’s Manual | * Active Steering Assist is temporarily unavailable.
The ambient conditions are outside the system limits (/ page 168). As soon as the ambient conditions are within the system limits, the system will become available again. # Drive on. # Check the tire pressure if necessary. |
| Active Steering Assist Inop- erative | * Active Steering Assist is malfunctioning. Active Distance Assist DISTRONIC remains available.
# Consult a qualified specialist workshop. |
| Active Steering Asst. Cur- rently Unavailable Due to Multiple Emergency Stops | * Active Steering Assist is temporarily unavailable due to multiple emergency stops.
# Take over the steering and stop in accordance with the traffic conditions. # Switch the ignition off and switch it back on. Active Steering Assist is available once more. |
| Beginning Emergency Stop | * Your hands are not on the steering wheel. An emergency stop is being initiated (/ page 170).
# Put your hands back on the steering wheel. You can cancel the deceleration at any time by performing one of the following actions: R Steering R Braking or accelerating R Deactivating Active Distance Assist DISTRONIC |
| Display messages Possible causes/consequences and M Solutions | |
|
|
* Active Steering Assist has reached the system limits. You have not steered independently for a considerable period of time. # Take over the steering and drive on in accordance with the traffic conditions. |
| Traffic Sign Assist Cur- rently Unavailable See Operator’s Manual | * Traffic Sign Assist is temporarily unavailable.
When the cause of the problem is no longer present, the system will be available again. |
| Traffic Sign Assist Inopera- tive | * Traffic Sign Assist is malfunctioning. # Stop the vehicle in accordance with the traffic conditions and restart the engine. # If the display message still appears, consult a qualified specialist workshop. |
| Blind Spot Assist Currently Unavailable See Operator’s Manual | * Blind Spot Assist is temporarily unavailable.
The system limits have been reached. # Drive on. or |
| Blind Spot Assist Inoperative | * Blind Spot Assist is malfunctioning. # Consult a qualified specialist workshop. |
| Display messages Possible causes/consequences and M Solutions | |
| Active Blind Spot Assist Currently Unavailable See Operator’s Manual | * Active Blind Spot Assist is temporarily unavailable. The system limits have been reached. Once the cause of the problem is no longer present, the system will be available again.
# Drive on. or |
| Active Blind Spot Assist Inoperative | * Active Blind Spot Assist is malfunctioning. # Consult a qualified specialist workshop. |
| Active Lane Keeping Assist Currently Unavailable See Operator’s Manual | * Active Lane Keeping Assist is temporarily unavailable.
The ambient conditions are outside the system limits. # Drive on. |
| Active Lane Keeping Assist Inoperative | * Active Lane Keeping Assist is malfunctioning. # Consult a qualified specialist workshop. |
| Display messages Possible causes/consequences and M Solutions | |
|
Currently Unavailable Radar Sensors Dirty |
* The radar sensor system is malfunctioning. Possible causes:
R Dirt on the sensors Driving systems and driving safety systems may be malfunctioning or temporarily unavailable. # Pull over and stop the vehicle safely as soon as possible, paying attention to road and traffic conditions. |
| Display messages Possible causes/consequences and M Solutions | |
|
Currently Unavailable Cam- era View Restricted |
* The camera view is restricted. Possible causes:
R Dirt on the windshield in the camera’s field of vision Driving systems and driving safety systems may be malfunctioning or temporarily unavailable. If the display message does not disappear: |
| Display messages | Possible causes/consequences and M Solutions |
|
Malfunction Drive at Max. 50 mph |
* The adjustable damping is malfunctioning. The vehicle’s handling characteristics may be affected.
# Do not drive at speeds greater than 50 mph (80 km/h). |
| Parking Assist and PARKTRONIC Inoperative See Operator’s Manual | * Vehicles with Active Parking Assist: Active Parking Assist and Parking Assist PARKTRONIC are malfunctioning. Vehicles without Active Parking Assist: Parking Assist PARKTRONIC is malfunctioning.
# Stop the vehicle in accordance with the traffic conditions and restart the engine. |
Driving safety systems
| Display messages | Possible causes/consequences and M Solutions | |||
|
|
* ABS and ESP® are temporarily unavailable.
Other driving systems and driving safety systems (e.g. BAS) may also be temporarily unavailable. |
|||
| & WARNING Risk of skidding if ABS and ESP® are malfunctioning | ||||
| Currently Unavailable See Operator’s Manual | ||||
| The wheels may lock during braking and ESP® does not perform any vehicle stabilization. The steerability and braking characteristics are heavily impaired and the braking distance may increase. In addition, other driving safety systems are switched off.
# Drive carefully on a suitable stretch of road, making slight steering movements at a speed above 19 mph (30 km/h). |
||||
| Display messages | Possible causes/consequences and M Solutions | |||
|
|
* ABS and ESP® are malfunctioning.
Other driving systems and driving safety systems (e.g. BAS) may also be malfunctioning. |
|||
| & WARNING Risk of skidding if ABS and ESP® are malfunctioning | ||||
| Inoperative See Operator’s Manual | ||||
| The wheels may block during braking and ESP® does not perform any vehicle stabilization.
The steerability and braking characteristics are heavily impaired and the braking distance may increase. In addi‐ tion, other driving safety systems are switched off. |
||||
| # Drive on carefully. | ||||
| # Have ABS and ESP® checked immediately at a qualified specialist workshop. | ||||
|
Currently Unavailable See Operator’s Manual |
* ESP® is temporarily unavailable. Other driving systems and driving safety systems (e.g. BAS) may also be malfunctioning.
& WARNING Risk of skidding if ESP is malfunctioning® |
|||
| Display messages Possible causes/consequences and M Solutions | |||
| # Drive carefully on a suitable stretch of road, making slight steering movements at a speed above 19 mph (30 km/h).
# If the display message does not disappear, consult a qualified specialist workshop immediately. Drive care‐ fully. |
|||
|
Inoperative See Operator’s Manual |
* ESP® is malfunctioning. Other driving systems and driving safety systems (e.g. BAS) may also be malfunctioning. The brake system will continue to operate normally. The braking distance in an emergency braking situation can increase. |
||
| & WARNING Risk of skidding if ESP® is malfunctioning | |||
| If ESP® is malfunctioning, ESP® cannot carry out vehicle stabilization. In addition, other driving safety systems are switched off.
# Drive on carefully. |
|||
| Display messages | Possible causes/consequences and M Solutions |
|
|
* EBD, ABS and ESP® are malfunctioning. Other driving systems and driving safety systems (e.g. BAS) may also be malfunctioning.
& WARNING Risk of skidding if EBD, ABS and ESP® are malfunctioning The steerability and braking characteristics are heavily impaired and the braking distance may increase. In addi‐ tion, other driving safety systems are switched off. |
| Inoperative See Operator’s Manual | |
|
Active Brake Assist Functions Currently Limited See Operator’s Manual |
* Vehicles with the Driving Assistance Package: Active Brake Assist with cross-traffic function, Evasive Steering Assist or PRE‑SAFE® PLUS are temporarily unavailable or only partially available. Vehicles without the Driving Assistance Package: Active Brake Assist is temporarily unavailable.
# Drive on. |
| Display messages | Possible causes/consequences and M Solutions |
| Active Brake Assist Func- tions Limited See Opera- tor’s Manual | * Vehicles with the Driving Assistance Package: Active Brake Assist with cross-traffic function, Evasive Steering Assist or PRE‑SAFE® PLUS are temporarily unavailable or only partially available.
Vehicles without the Driving Assistance Package: Active Brake Assist is temporarily unavailable or only partially available. # Consult a qualified specialist workshop. |
|
Mercedes me connect |
|
| Display messages | Possible causes/consequences and M Solutions |
| Device Detected at Diagnostics Connection See Operator’s Manual | * The vehicle functions for malfunction detection are restricted.
At least one of the main functions of the Mercedes me connect system is malfunctioning. |
 Inoperative |
* At least one of the main functions of the Mercedes me connect system or of the SOS emergency call system is malfunctioning. # Consult a qualified specialist workshop. |
Battery
| Display messages | Possible causes/consequences and M Solutions |
|
12 V Battery See Opera- tor’s Manual |
* The engine is off and the charge level is too low. # Switch off electrical consumers that are not required.
To charge the 12 V battery: # Leave the engine running for a few minutes, or drive an extended distance. |
|
|
* The 12 V battery is not being charged. * NOTE Possible engine damage if you continue driving
# Do not continue driving under any circumstances. |
| Display messages | Possible causes/consequences and M Solutions |
|
Stop Vehicle See Opera- tor’s Manual |
* The 12 V battery is no longer being charged and the charge level is too low. * NOTE Possible engine damage if you continue driving
# Do not continue driving under any circumstances. |
|
Stop Vehicle Leave Engine Running |
* The 12 V battery charge level is too low.
# Stop the vehicle immediately in accordance with the traffic conditions. Do not continue driving. |
Tire pressure monitor
| Display messages | Possible causes/consequences and M Solutions | ||
| Tire Press. Monitor Currently Unavailable | * There is interference from a powerful radio signal source As a result, no signals from the tire pressure sensors are being received. The tire pressure monitoring system is temporarily unavailable. The tire pressure monitoring system will restart automatically as soon as the cause has been rectified. # Drive on. |
||
| Tire Press. Monitor Inopera- tive | * The tire pressure monitoring system is malfunctioning. | ||
| & WARNING There is a risk of an accident if the tire pressure monitoring system is malfunctioning | |||
| The tire pressure monitoring system cannot issue a warning if there is pressure loss in one or more of the tires. Tires with insufficient tire pressure may impair the driving characteristics as well as steering and braking.
# Have the tire pressure monitoring system checked at a qualified specialist workshop. |
|||
| Tire Pressure Monitor Inop- erative No Wheel Sensors | * The wheels installed do not have suitable tire pressure sensors. The tire pressure monitoring system is deactivated. # Install wheels with suitable tire pressure sensors. |
||
Wheel Sensor(s) Missing |
* There is no signal from the tire pressure sensors of one or more wheels. No pressure value is displayed for the affected tire. # Have the faulty tire pressure sensor replaced at a qualified specialist workshop. |
||
| Display messages | Possible causes/consequences and M Solutions |
|
Check Tires |
* The tire pressure in one or more tires has dropped significantly. The wheel position will be displayed.
& WARNING Risk of an accident due to insufficient tire pressure R The tires can burst. You could then lose control of the vehicle. # Observe the recommended tire pressures. |
|
Please Correct Tire Pres- sure |
* The tire pressure is too low in at least one of the tires, or the difference in tire pressure between the individual wheels is too great. # Check the tire pressure and add air, if necessary. # When the tire pressure is correct, restart the tire pressure monitor. |
| Display messages | Possible causes/consequences and M Solutions |
|
Warning Tire Malfunction |
* The tire pressure in one or more tires has dropped suddenly. The wheel position will be displayed.
& WARNING Risk of an accident from driving with a flat tire You could then lose control of the vehicle. # Do not drive with a flat tire. Notes in the event of a flat tire (/ page 266). # Stop the vehicle in accordance with the traffic conditions. |
| Tires Overheated | * At least one tire is overheating. The affected tires are displayed in red. At temperatures close to the limit value, the tires are displayed in yellow.
& WARNING Risk of an accident from driving with overheated tires Overheated tires can burst. |
| Display messages | Possible causes/consequences and M Solutions | ||
| # Reduce speed so that the tires cool down. | |||
| Decrease Speed | * At least one tire is overheating. The affected tires are displayed in red. At temperatures close to the limit value, the tires are displayed in yellow. | ||
| & WARNING Risk of an accident from driving with overheated tires | |||
| Overheated tires can burst.
# Reduce speed so that the tires cool down. |
|||
Tire pressure loss warning system
| Display messages | Possible causes/consequences and M Solutions |
| Check Tire Pressure Soon | * Canada only:
The tire pressure loss warning system has detected a significant loss of pressure. & WARNING Risk of an accident due to insufficient tire pressure R The tires can burst. R The tires can wear excessively and/or unevenly. R The driving characteristics as well as the steering and braking may be greatly impaired. |
| Display messages Possible causes/consequences and M Solutions | |
| You could then lose control of the vehicle. # Observe the recommended tire pressures. # Adjust the tire pressure if necessary. # Stop the vehicle in accordance with the traffic conditions. # Check the tire pressure (/ page 288) and the tires. # When the tire pressure is correct, restart the tire pressure loss warning system (/ page 294). |
|
| Check Tire Pressure Then Restart Run Flat Indicator | * Canada only:
The tire pressure loss warning system generated a display message and has not been restarted since. |
| Run Flat Indicator Inopera- tive | * Canada only:
The tire pressure loss warning system is malfunctioning. |
Engine oil
| Display messages Possible causes/consequences and M Solutions | |
Check Engine Oil Level (Add 1 quart) |
* The engine oil level has dropped to the minimum level.
* NOTE Engine damage caused by driving with insufficient engine oil # Avoid long journeys with insufficient engine oil. # When next refueling, add 1.1 US qt (1 l) of engine oil (/ page 254). Notes on engine oil (/ page 326). |
|
Engine Oil Reduce Oil Level |
* The engine oil level is too high.
* NOTE Engine damage caused by driving with excess engine oil # Avoid long journeys with excess engine oil. # Consult a qualified specialist workshop immediately and have the engine oil level reduced. |
|
Engine Oil Level Low Stop Vehicle Turn Engine Off |
* The engine oil level is too low.
* NOTE Engine damage caused by driving with insufficient engine oil # Avoid long journeys with insufficient engine oil. # Stop the vehicle immediately in accordance with the traffic conditions. Do not continue driving. |
| Display messages | Possible causes/consequences and M Solutions | ||
| #
# # |
Switch off the engine.
Add 1.1 US qt (1 l) of engine oil (/ page 254). Check the engine oil level. |
||
| Notes on engine oil (/ page 326). | |||
|
Engine Oil Pressure Stop Switch Off Engine |
* The oil pressure is too low.
* NOTE Engine damage caused by driving with insufficient oil pressure # Avoid driving with insufficient oil pressure. # Stop the vehicle immediately in accordance with the traffic conditions. Do not continue driving. # Consult a qualified specialist workshop. |
||
|
Engine Oil Level Cannot Be Measured |
* The electrical connection to the oil level sensor has been interrupted or the oil level sensor is faulty.
# Consult a qualified specialist workshop. |
||
Warning and indicator lamps
Overview of indicator and warning lamps
Some systems will perform a self-test when the ignition is switched on. Some indicator and warning lamps may briefly light up or flash. This behavior is non-critical. These indicator and warning lamps indicate a malfunction only if they light up or flash after the engine has been started or during a journey.
Instrument Display (standard)
Widescreen Cockpit Instrument Display
Depending on the display setting, the positions of the indicator lamps on the Instrument Display may differ from the example shown.
Indicator and warning lamps:
Restraint system
Seat belt- Power steering
Vehicles with a Widescreen Cock‐pit: coolant temperature
Check Engine
Electrical malfunction- Reserve fuel with fuel filler flap location indicator
- USA: electric parking brake (red)
- Canada: electric parking brake (red)
- Electric parking brake (yellow)
USA: Recuperative Brake System- Canada: brakes (yellow)
- USA: brakes (red)
- Canada: brakes (red)
Distance warning
ABS
ESP®
ESP® OFF- Tire pressure monitoring system
Parking lamps
Low beam
High beam
Turn signal lights
Rear fog light
Occupant safety
| Warning/indicator lamp | Possible causes/consequences and M Solutions |
|
Restraint system warning lamp |
* The red restraint system warning lamp is lit while the engine is running. The restraint system is malfunctioning (/ page 37). &WARNING Risk of injury due to malfunctions in the restraint system Components in the restraint system may be activated unintentionally or not deploy as planned in an accident.
# Have the restraint system checked and repaired immediately at a qualified specialist workshop. |
| Warning/indicator lamp | Possible causes/consequences and M Solutions |
|
Seat belt warning lamp flashes |
* The red seat belt warning lamp flashes and an intermittent warning tone sounds.
The driver or front passenger has not fastened his/her seat belt while the vehicle is in motion. There are objects on the front passenger seat. |
|
Seat belt warning lamp lights up |
* The red seat belt warning lamp lights up for six seconds once the engine has started. In addition, an intermittent warning tone may sound. The red seat belt warning lamp reminds the driver and front passenger to fasten their seat belts.
# Fasten your seat belt (/ page 40). |
|
Vehicle |
|
| Warning/indicator lamp | Possible causes/consequences and M Solutions |
|
Power steering warning lamp (red) |
* The red power steering system warning lamp is lit while the engine is running. The power assistance or the steering itself is malfunctioning. &WARNING Risk of accident if steering capability is impaired If the steering does not function as intended, the vehicle’s operating safety is jeopardized. |
| Warning/indicator lamp | Possible causes/consequences and M Solutions |
| # Pull over and stop the vehicle safely as soon as possible, paying attention to road and traffic conditions. Do not continue driving under any circumstances.
# Consult a qualified specialist workshop. # Note the messages on the multifunction display. |
|
|
Engine |
|
| Warning/indicator lamp | Possible causes/consequences and M Solutions |
|
Coolant warning lamp (red) |
* The red coolant warning lamp is lit while the engine is running. Possible causes:
R The temperature sensor is malfunctioning |
| Warning/indicator lamp | Possible causes/consequences and M Solutions | ||
| &WARNING Danger of burns when opening the hood | |||
| If you open the hood when the engine has overheated or during a fire in the engine compartment, you could come into contact with hot gases or other escaping operating fluids.
# Before opening the hood, allow the engine to cool down. # In the event of a fire in the engine compartment, keep the hood closed and call the fire service. |
|||
| # Stop the vehicle immediately in accordance with the traffic conditions and switch off the engine. Do not continue driving under any circumstances.
# Note the messages on the multifunction display. If the coolant temperature display is at the lower end of the temperature scale: # Consult a qualified specialist workshop. If the coolant temperature display is at the upper end of the temperature scale: # Exit the vehicle and keep a safe distance from it until the engine has cooled down. # Check the coolant level (/ page 255). # Make sure that the air supply to the radiator is not obstructed. # Avoiding high loads on the engine, drive to the nearest qualified specialist workshop. In doing so, ensure that the coolant temperature display remains below the red area. |
|||
|
Coolant warning lamp (yel‐ low) |
* The yellow coolant warning lamp is lit while the engine is running. Possible causes:
R The temperature sensor is malfunctioning |
|
Engine diagnosis warning lamp |
* The yellow Check Engine warning lamp is lit while the engine is running.
A malfunction has occurred in the engine, the exhaust system or the fuel system. # Have the vehicle checked as soon as possible at a qualified specialist workshop. |
|
Electrical malfunction warn‐ ing lamp |
* The red electrical fault warning lamp is lit. There is a fault in the electrics. # Note the messages on the multifunction display. |
|
Fuel reserve warning lamp flashes |
* The yellow fuel reserve warning lamp lights up while you are driving.
There has been pressure loss in the fuel system. The fuel filler cap is not closed correctly or the fuel system is leak‐ ing. If the fuel filler cap has already been closed correctly:# Consult a qualified specialist workshop. |
Fuel reserve warning lamp lights up |
* The yellow fuel reserve warning lamp lights up while the engine is running. The fuel supply has dropped into the reserve range. # Refuel. |
Brakes
| Electric parking brake indi‐ cator lamp (red) (USA only)
Electric parking brake indi‐ cator lamp (red) (Canada only)
The electric parking brake (yellow) indicator lamp |
*The red electric parking brake indicator lamp flashes or is lit.
The yellow electric parking brake indicator lamp also lights up in the event of a malfunction. |
|
Recuperative Brake System warning lamp (USA only)
Brakes warning lamp (yellow) (Canada only) |
*The yellow é warning lamp (USA only) or the yellow J brakes warning lamp (Canada only) is lit while the engine is running.
&WARNING Risk of an accident due to a brake system malfunction If the brake system is malfunctioning, braking characteristics may be impaired. # Drive on carefully. |
| Warning/indicator lamp | Possible causes/consequences and M Solutions | ||
|
Brake warning lamp (USA only)
Brake system warning lamp (Canada only) |
* The red brake system warning lamp is lit while the engine is running. Possible causes: R The brake force boosting is malfunctioning and the braking characteristics may be affected. R There is insufficient brake fluid in the brake fluid reservoir. |
||
| &WARNING Risk of an accident due to low brake fluid level | |||
| If the brake fluid level is too low, the braking effect and the braking characteristics may be impaired.
# Pull over and stop the vehicle safely as soon as possible, paying attention to road and traffic conditions. Do not continue driving under any circumstances. |
|||
Driving systems
Active Brake Assist warning lamp |
* The white Active Brake Assist warning lamp is lit. The system is switched off or unavailable. |
|
Warning lamp for distance warning function |
* The red distance warning lamp lights up while the vehicle is in motion. The distance to the vehicle in front is too small for the speed selected.
If there is an additional warning tone, you are approaching an obstacle at too high a speed. |
Driving safety systems
| Warning/indicator lamp | Possible causes/consequences and M Solutions | ||
|
ABS warning lamp |
* The yellow ABS warning lamp is lit while the engine is running. ABS is malfunctioning. If there is an additional warning tone, EBD is malfunctioning. Other driving systems and driving safety systems may also be malfunctioning. # Note the messages on the multifunction display. |
||
| &WARNING There is a risk of skidding if EBD or ABS is malfunctioning | |||
| The wheels may lock during braking.
The steerability and braking characteristics are heavily impaired and the braking distance may increase. In addition, other driving safety systems are switched off. # Drive on carefully. # Have the brake system checked immediately at a qualified specialist workshop. |
|||
|
ESP® warning lamp flashes |
* The yellow ESP® warning lamp flashes while the vehicle is in motion. One or more wheels has reached its grip limit. # Adapt your driving style to suit the road and weather conditions. |
||
| Warning/indicator lamp | Possible causes/consequences and M Solutions | ||
|
ESP® warning lamp lights up |
* The yellow ESP® warning lamp is lit while the engine is running. ESP® is malfunctioning. Other driving systems and driving safety systems (e.g. BAS) may also be malfunctioning. # Note the messages on the multifunction display. |
||
| &WARNING Risk of skidding if ESP® is malfunctioning | |||
| If ESP® is malfunctioning, ESP® cannot carry out vehicle stabilization. In addition, other driving safety systems are switched off.
# Drive on carefully. # Have ESP® checked at a qualified specialist workshop. |
|||
|
ESP® OFF warning lamp |
* The yellow ESP® OFF warning lamp is lit while the engine is running. ESP® is deactivated. Other driving systems and driving safety systems may also be inoperative.
&WARNING Risk of skidding when driving with ESP® deactivated # Drive on carefully. |
||
| Warning/indicator lamp | Possible causes/consequences and M Solutions | ||
|
If ESP® cannot be activated, ESP® is malfunctioning. |
|||
|
Tire pressure monitor |
|||
| Warning/indicator lamp | Possible causes/consequences and M Solutions | ||
|
Tire pressure monitoring system warning lamp flashes |
*The yellow tire pressure monitor warning lamp (pressure loss/malfunction) flashes for approximately one minute and then remains lit. The tire pressure monitor is malfunctioning. |
||
| &WARNING There is a risk of an accident if the tire pressure monitoring system is malfunctioning | |||
| The tire pressure monitoring system cannot issue a warning if there is pressure loss in one or more of the tires. Tires with insufficient tire pressure may impair the driving characteristics as well as steering and braking. # Have the tire pressure monitoring system checked at a qualified specialist workshop. |
|||
|
Tire pressure monitoring system warning lamp lights up |
*The yellow tire pressure monitoring system warning lamp (pressure loss/malfunction) is lit. The tire pressure monitoring system has detected tire pressure loss in at least one of the tires.
&WARNING Risk of an accident due to insufficient tire pressure R The tires can burst. You could then lose control of the vehicle. # Observe the recommended tire pressures. |
FAQs
A issue with the vehicle’s charging system is indicated by the red battery warning light. It could be caused by a bad battery, alternator, or other components. To prevent future failures, it’s critical to have the car checked out right away if this light turns on.
The yellow Check Engine Light (CEL), often known as the engine check light, alerts the driver to a possible problem with the engine or emissions system. Even if it might not be an emergency, it’s crucial to have it examined by a trained specialist to avoid future issues.
Low engine oil pressure is indicated by the red oil can warning light. If this light comes on, stop the car right away in a secure area, and check the oil. Driving with low oil pressure may seriously harm your engine.
The overheated engine is indicated by the yellow coolant temperature indicator. Low coolant levels, a flawed cooling system, or a broken temperature sensor might all be at blame. Before fixing the problem, halt the car and let the engine cool.
A potential problem with the power steering system is indicated by the yellow steering wheel light. It can be caused by a system breakdown or insufficient power steering fluid. Have a professional examine the car to identify and fix the issue.
A braking system issue is indicated by the red brake warning light. It can be caused by low brake fluid levels or a problem with the braking system. Avoid operating the vehicle, and have it towed to an authorized repair facility.
The yellow warning light for the ABS (Anti-lock Braking System) denotes a problem with the ABS system. While the ABS function could be compromised, the conventional brakes might still operate. Hire an expert to inspect the system as soon as you can.
A problem with the vehicle’s stability control system is indicated by the yellow ESP (Electronic Stability Program) warning light. In difficult driving circumstances, this mechanism aids in stability maintenance. To make sure the system is operating properly, get it examined.
The engine’s auto start-stop feature is activated when the green Auto Start-Stop light is on. This function helps save gasoline by automatically turning off the engine when the car comes to a stop.
The car is being driven sustainably, as evidenced by the green Eco driving light. It promotes efficient driving practices.
The yellow TPMS light denotes low tire pressure or a sensor issue in one or more tires. Visit a service shop for a system checkup or check the tire pressures and adjust them as necessary.
The low AdBlue® fluid level is indicated by the yellow AdBlue® light. Vehicles using Selective Catalytic Reduction (SCR) utilize AdBlue® to cut emissions. To guarantee compliance with pollution laws, fill the AdBlue® tank as soon as possible.
The high beam headlights are on as shown by the blue high beam light. When approaching other cars, keep in mind to switch to low lights to prevent blinding the drivers.
The activated turn signal is shown by the green turn signal arrow light. It aids in letting other drivers know what your objectives are.
An issue with the airbag system is indicated by the yellow airbag warning light. It’s critical to get the airbag system checked out and fixed by a professional since malfunctioning airbags may not deploy properly in the event of a collision.
Useful Links
View Full Manual: Mercedes-Benz A-CLASS SEDAN 2021 User Manual
Mercedes-Benz A-CLASS SEDAN 2021 Seats and Steering Wheel User Manual