Mercedes-Benz E-Class Quiz
On-board computer and displays

Safety systems

In this manual: On-board computer and displays
Introduction — 5At a glance — 6Safety — 25Opening and Closing — 17Seats, steering wheel and mirrors — 12Lights and windshield wipers — 11Climate Control — 11Driving and parking — 44On-board computer and displays — 29Stowing and Useful Information. Good to Know — 1Stowing and Useful Information. Storage Options — 10Stowage and convenience features. Convenience features — 7Maintenance and care — 11Roadside assistance — 13Wheels and tires — 13Technical data — 13
~8min read

The safety systems in the Mercedes E-Class (4th gen, W212, 2009–2016) provide a high level of protection through intelligent assistance functions. This section describes typical warning messages, their causes and the recommended responses in order to maintain vehicle stability and braking performance in the event of a malfunction. Clear instructions help the driver continue driving safely.

Display messages Possible causes/consequences and solutions
Currently not available, see owner's manual ABS (Anti-lock Braking System), ESP (Electronic Stability Program), BAS (Brake Assist System), HOLD function, PRE-SAFE, Hill Start Assist and ESP Trailer Stabilisation are temporarily unavailable.

Adaptive Brake Light, BAS PLUS with Cross-Traffic Assist, COLLISION PREVENTION ASSIST PLUS, PRE-SAFE PLUS and PRE-SAFE Brake may also have failed.

In addition, the warning lamps, andflashes in the instrument cluster.

ATTENTION ASSIST is deactivated.

The on-board voltage may be too low, for example.

WARNING

The brake system continues to work with normal effect, but without the functions listed above. The wheels may therefore lock, for example during full braking.

This significantly impairs steering ability and braking performance. Braking distance may increase in emergency braking situations.

If ESP is not ready for operation, ESP does not stabilise the vehicle.

There is an increased risk of skidding and accidents!

Continue driving carefully.
  • When the display message goes out, the functions listed above are available again.

    If the multifunction display continues to show the display message:

    Continue driving carefully.

    Consult a qualified specialist workshop.

    		•
    without function, see Operator's Manual ABS, ESP, BAS, HOLD function, PRE-SAFE, Hill Start Assist and ESP Trailer Stabilization are not available due to a malfunction.

    Adaptive Brake Light, BAS PLUS with Cross-Traffic Assist, COLLISION PREVENTION ASSIST PLUS, PRE-SAFE PLUS and PRE-SAFE Brake may also have failed.

    In addition, the warning lamps, , andflashes in the instrument cluster.

    ATTENTION ASSIST is deactivated.

    WARNING

    The brake system continues to work with normal effect, but without the functions listed above. The wheels may therefore lock, for example during full braking.

    This significantly impairs steering ability and braking performance. Braking distance may increase in emergency braking situations.

    If ESP is not ready for operation, ESP does not stabilise the vehicle.

    There is an increased risk of skidding and accidents!

    Continue driving carefully.

    Visit a qualified workshop immediately.
    without function, see Operator's Manual ESP, BAS, HOLD function, PRE-SAFE, Hill Start Assist and ESP Trailer Stabilization are not available due to a malfunction.

    Adaptive Brake Light, BAS PLUS with Cross-Traffic Assist, COLLISION PREVENTION ASSIST PLUS, PRE-SAFE PLUS and PRE-SAFE Brake may also have failed.

    In addition, the warning lampsandflashes in the instrument cluster.

    For example, the self-diagnosis has not yet been completed.

    ATTENTION ASSIST is deactivated.

    WARNING

    The brake system continues to operate with normal effect, but without the functions listed above.

    As a result, braking distance may increase in emergency braking situations.

    If ESP is not ready for operation, ESP does not stabilise the vehicle.

    There is an increased risk of skidding and accidents!

    Continue driving carefully.

    Consult a qualified specialist workshop.
    without function, see Operator's Manual

    EBD (Electronic Brake-force Distribution), ABS, ESP, BAS, HOLD function, PRE-SAFE, Hill Start Assist and ESP Trailer Stabilization are not available due to a malfunction.

    Adaptive Brake Light, BAS PLUS with Cross-Traffic Assist, COLLISION PREVENTION ASSIST PLUS, PRE-SAFE PLUS and PRE-SAFE Brake may also have failed.

    In addition, the warning lamps, andin the instrument cluster and a warning tone sounds.

    WARNING

    The brake system continues to operate with normal effect, but without the functions listed above. The front and rear wheels may therefore lock, for example during full braking.

    This significantly impairs steering ability and braking performance. Braking distance may increase in emergency braking situations.

    If ESP is not ready for operation, ESP does not stabilise the vehicle.

    There is an increased risk of skidding and accidents!

    Continue driving carefully.

    Visit a qualified workshop immediately.
    Brake immediately A malfunction has occurred with the HOLD function switched on.

    or

    You have the HOLD function switched on and
    • open the driver's door and release the seat belt, or
    • switch off the engine.
    In addition, a regular horn tone may sound. If you try to lock the vehicle, the horn tone becomes more intense.

    You cannot start the engine.

    Taking the traffic situation into account, immediately press the brake pedal firmly until the display message goes out.

    Secure the vehicle against rolling away.

  • You can start the engine again.
    		•
    Release the parking brake

    You are driving with the parking brake applied. A warning tone also sounds.

    Release the parking brake.
    Checking the brake fluid level

    There is too little brake fluid in the brake fluid reservoir.

    In addition, the red warning lampin the instrument cluster and a warning tone sounds.

    WARNING

    Braking effect may be impaired.

    There is a risk of accidents!

    Stop safely as soon as possible. Do not continue driving!

    Secure the vehicle against rolling away.

    Contact a qualified workshop.

    Do not top up brake fluid. This will not rectify the fault.
    Brake pad wear The brake pads have reached the wear limit.

    Consult a qualified specialist workshop.
    without function

    One or more main functions of the Mercedes-Benz Contact system are faulty.

    Have the system checked at a qualified workshop.
    COLLISION PREVENTION ASSIST PLUS currently not available, see Operator's Manual

    COLLISION PREVENTION ASSIST PLUS is temporarily not ready for operation. Possible causes:

    • The radar sensor system is temporarily not ready for operation, e.g. due to electromagnetic radiation near television and radio transmitter stations or other radiation sources.
    • The system is outside the operating temperature range.
    • The vehicle electrical system voltage is too low.
    If the causes above do not apply, the display message goes out.

    COLLISION PREVENTION ASSIST PLUS is ready for operation again.

    If the display message does not go out:

    Stop safely.

    Secure the vehicle against rolling away.

    Restart the engine.
    Collision Prevention Assist Plus without function COLLISION PREVENTION ASSIST PLUS is not available due to a malfunction. The Adaptive Brake Assist may also have failed.

    Consult a qualified specialist workshop.
    PRE-SAFE without function, see Operator's Manual

    Important PRE-SAFE functions have failed. All other occupant protection systems, e.g. the airbags, are still available.

    Visit a qualified workshop immediately.
    PRE-SAFE functionality currently limited, see Operator's Manual PRE-SAFE PLUS or the PRE-SAFE Brake is temporarily not ready for operation.

    Possible causes:

    • The function is impaired by heavy precipitation.
    • The radar sensor system is temporarily not ready for operation, e.g. due to electromagnetic radiation near television and radio transmitter stations or other radiation sources.
    • AMG vehicles: ESP is switched off.
    • The system is outside the operating temperature range.
    • The vehicle electrical system voltage is too low.
    If the causes above do not apply, the display message goes out.

    PRE-SAFE PLUS and the PRE-SAFE Brake are ready for operation again.

    If the display message does not go out:

    Stop safely.

    Secure the vehicle against rolling away.

    Restart the engine.

    AMG vehicles: switch ESP back on.
    PRE-SAFE functionality limited, see Operator's Manual PRE-SAFE PLUS or the PRE-SAFE Brake is not available due to a malfunction. BAS PLUS with Cross-Traffic Assist may also have failed.

    Consult a qualified specialist workshop.
    Radar sensor soiled, see Operator's Manual At least one of the following driving systems or driving safety systems is temporarily not or only partially ready for operation:
    • COLLISION PREVENTION ASSIST PLUS
    • PRE-SAFE Brake
    • PRE-SAFE PLUS
    • Active Lane Keeping Assist
    • Active Blind Spot Assist
    • DISTRONIC PLUS with Steering Assist and Stop&Go Pilot
    If the front radar sensor is soiled, the Active Blind Spot Assist will not perform course-correcting braking intervention.

    Possible causes:

    • The sensors in the radiator grille and/or in the bumpers are soiled.
    • The function of the driving system or driving safety system is impaired by heavy precipitation.
    A warning tone also sounds.

    If the causes above do not apply, the display message goes out. All driving systems or driving safety systems are ready for operation again.

    If the display message does not go out:

    Stop safely.

    Secure the vehicle against rolling away.

    Switch off the engine.

    Clean the sensors at the following locations:

    • in the radiator grille
    • in the front bumper
    • in the rear bumper, especially in the center of the rear bumper
    Restart the engine.
  • The display message goes out.
    		•

    If the multifunction display shows the symbol, the belt tongue is latched in the buckle at a rear seat position.

    Further information on the rear seat belt status display.
    If the multifunction display shows the symbol, the belt tongue is not latched in the buckle at a rear seat position.

    WARNING

    If you do not fasten the seat belt correctly or the belt tongue does not latch properly in the buckle, the seat belt may not provide its intended protection.

    There is an increased risk of injury!

    If necessary, ask rear occupants to fasten their seat belts.

    Note further information on the rear seat belt status display.
    Restraint system malfunction, visit workshop

    The restraint system is faulty. The warning lamp also lights upflashes in the instrument cluster.

    WARNING

    The airbags or belt tensioners may either trigger unintentionally or fail to trigger in an accident.

    There is an increased risk of injury!

    Consult a qualified specialist workshop.

    Observe further information on the restraint system.
    Front left fault: visit a workshop or front right fault: visit a workshop The restraint system has a fault at the front left or right. In addition, the warning lamp lights upflashes in the instrument cluster.

    WARNING

    The airbags or belt tensioners may either trigger unintentionally or fail to trigger in an accident.

    There is an increased risk of injury!

    Consult a qualified specialist workshop.
    Rear left fault: visit a workshop or rear right fault: visit a workshop The restraint system has a fault at the rear left or right. In addition, the warning lamp lights upflashes in the instrument cluster.

    WARNING

    The airbags or belt tensioners may either trigger unintentionally or fail to trigger in an accident.

    There is an increased risk of injury!

    Consult a qualified specialist workshop.
    Rear center fault: visit a workshop The restraint system has a fault at the rear center. In addition, the warning lamp lights upflashes in the instrument cluster.

    WARNING

    The airbags or belt tensioners may either trigger unintentionally or fail to trigger in an accident.

    There is an increased risk of injury!

    Consult a qualified specialist workshop.
    Windowbag left fault: visit a workshop or Windowbag right fault: visit a workshop

    The left or right Windowbag has a fault.

    In addition, the warning lamp lights upflashes in the instrument cluster.

    WARNING

    The left or right Windowbag may deploy unintentionally or fail to deploy in an accident.

    There is an increased risk of injury!

    Consult a qualified specialist workshop.

    The Mercedes E-Class W212 (model years 2009–2016) offers state-of-the-art safety systems such as ABS, ESP and PRE-SAFE, which support the driver in critical situations. Even if a fault is present, the basic braking system still works, but with limitations in stability and braking distance.

    The clear display of warning lamps and display messages helps the driver recognize problems early and respond appropriately. With these functions, Mercedes underlines its commitment to the highest level of safety in road traffic.

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