Safety systems

Display messages Possible causes/consequences and ► Solutions

Unavailable See Currently Unavailable See Operator's Manual

Risk of accident
ABS, ESP®, BAS, PRE-SAFE®, the HOLD function and hill start assist are temporarily unavailable.

BAS PLUS and PRE-SAFE® Brake may also have failed.

In addition, the up in warning lamps light up in the instrument cluster.

For example, the on-board voltage may be insufficient.

ATTENTION ASSIST is deactivated.

The brake system continues to function normally, but without the functions listed above. The wheels could therefore lock if you brake hard, for example.

•► Drive on carefully.

If the display message disappears, the functions mentioned above are available again.

If the display message continues to be displayed:

•► Drive on carefully.

•► Visit a qualified specialist workshop.

Operator's Manual Inoperative See Operator's Manual

Risk of accident
ABS, ESP®, BAS, PRE-SAFE®, the HOLD function and hill start assist are unavailable due to a malfunction.

BAS PLUS and PRE-SAFE® Brake may also have failed.

The (Canada only), (USA only)/ and  warning lamps in the instrument (Canada only),and  warning lamps in the instrument and cluster also light up. warning lamps in the instrument cluster also light up.

The brake system continues to function normally, but without the functions listed above. The wheels could therefore lock if you brake hard, for example.

ATTENTION ASSIST is deactivated.

•► Drive on carefully.
•► Visit a qualified specialist workshop immediately.

Operator's Manual Inoperative See Operator's Manual

Risk of accident
ESP®, BAS, PRE-SAFE®, the HOLD function and hill start assist are unavailable due to a malfunction.

BAS PLUS and PRE-SAFE® Brake may also have failed.

In addition, the light up in the warning lamps light up in the instrument cluster.

ATTENTION ASSIST is deactivated.

The brake system continues to function normally, but without the functions listed above.

•► Drive on carefully.
•► Visit a qualified specialist workshop.

Operator's Manual Inoperative See Operator's Manual

Risk of accident
EBD (electronic brake force distribution), ABS, ESP®, BAS, PRESAFE ®, the HOLD function and hill start assist are unavailable due to a malfunction.

BAS PLUS and PRE-SAFE® Brake may also have failed.

In addition, the light up in warning lamps light up in the instrument cluster and a warning tone sounds.

ATTENTION ASSIST is deactivated.

The brake system continues to function normally, but without the functions listed above. The wheels could therefore lock if you brake hard, for example.

•► Drive on carefully.
•► Visit a qualified specialist workshop immediately.

Wear Check Brake Pad Wear

The brake pads/linings have reached their wear limit.

•► Visit a qualified specialist workshop.

(USA only)

(Canada only)
Release Parking Brake

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

•► Release the parking brake.

(USA only)

(Canada only)
Check Brake Fluid Level

Risk of accident
There is not enough brake fluid in the brake fluid reservoir.

Additionally, the red (Canada only) (USA only)/ warning lamp lights up in the instrument cluster and a warning (Canada only) warning lamp lights up in the instrument cluster and a warning tone sounds.

•► 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.

•► Engage the parking brake.

•► Consult a qualified specialist workshop.

•► Do not add brake fluid. This will not rectify the malfunction.

WARNING
Driving with the message Check Brake Fluid Level displayed can result in an accident. Have your brake system checked immediately.

Do not add brake fluid before checking the brake system. Overfilling the brake fluid reservoir can result in spilling brake fluid on hot engine parts and the brake fluid catching fire. You can be seriously burned.

Display messages Possible causes/consequences and •►  Solutions

Inoperative Tele Aid Inoperative

USA only: one or more of the main functions in the mbrace system are malfunctioning.

Canada only: one or more of the main functions of the TELEAID system are malfunctioning.

•► USA only: have the mbrace system checked at a qualified specialist workshop.

•► Canada only: have the TELEAID system checked at a qualified specialist workshop.

PRE-SAFE Inoperative See Operator's Manual

Risk of injury
Important functions of PRE-SAFE® have failed. All other occupant safety systems, e.g. air bags, remain available.

•► Visit a qualified specialist workshop immediately.

PRE-SAFE Function Currently Limited See Oper.

Manual

Risk of accident PRE-SAFE® Brake is temporarily inoperative if:

 - the DISTRONIC PLUS cover in the radiator grill is dirty.
 - the sensors in the bumpers are dirty.
 - its function is impaired due to heavy rain or snow.
 - the radar sensor system is temporarily inoperative, e.g. due to electromagnetic radiation emitted by nearby TV or radio stations or other sources of electromagnetic radiation.

 - you switch off ESP® (AMG vehicles only).
 - the system is outside the operating temperature range.
 - the on-board voltage is too low.

PRE-SAFE® Brake is operational again and the display message disappears if:

 - the dirt (e.g. slush) drops away while the vehicle is in motion.
 - the system detects that the sensors are fully available again.
 - you switch ESP® on again (AMG vehicles only).
 - the system is within the operating temperature range.

If the display message continues to be displayed:

•► Clean the DISTRONIC PLUS cover in the radiator grill.

•► Clean the bumpers.

•► Restart the engine.

•► Wait until the battery is sufficiently charged.

PRE-SAFE Functions Limited See Operator's Manual

Risk of accident
PRE-SAFE® Brake is defective. BAS PLUS or the distance warning signal may also have failed.

•► Visit a qualified specialist workshop.

Service Required SRS Malfunction Service Required

Risk of injury
There is a malfunction in the SRS (Supplemental Restraint System). The lights up in the instrument warning lamp also lights up in the instrument cluster.

•► Visit a qualified specialist workshop.

Malfunction Front Left Malfunction Service Required or Front Right Malfunction Service Required

Risk of injury
SRS has malfunctioned at the front on the left or right. The warning lamp also lights up in the instrument cluster. warning lamp also lights up in the instrument cluster.

•► Visit a qualified specialist workshop.

Malfunction Rear Left Malfunction Service Required or Rear Right Malfunction Service Required

Risk of injury
SRS has malfunctioned at the rear on the left or right. The warning lamp also lights up in the instrument cluster. warning lamp also lights up in the instrument cluster.

•► Visit a qualified specialist workshop.

Malfunction Rear Center SRS Malfunction Service Required

Risk of injury
SRS has malfunctioned at the rear center. The also lights up in the instrument cluster. warning lamp also lights up in the instrument cluster.

•► Visit a qualified specialist workshop.

Airbag Malfunction Left Side Curtain Airbag Malfunction Service Required or Right Side Curtain Airbag Malfunction Service Required

Risk of injury
There is a malfunction in the left-hand and/or right-hand window curtain air bag. The also lights up in the warning lamp also lights up in the instrument cluster.

•► Visit a qualified specialist workshop.

WARNING
In the event a malfunction of the SRS is indicated as outlined above, the SRS may not be operational.

For your safety, we strongly recommend that you contact an authorized Mercedes-Benz Center immediately to have the system checked. Otherwise the SRS may not be activated when needed in an accident, which could result in serious or fatal injury, or it might deploy unexpectedly and unnecessarily which could also result in injury.

Display messages Possible causes/consequences and ► Solutions

Front Passenger Airbag Enabled See Operator's Manual

The front-passenger air bag is enabled during the journey, even though:

 - a child, a small adult or an object weighing less than the system's weight threshold is located on the front-passenger seat.
 - the front-passenger seat is unoccupied.

The system may detect objects or forces applying additional weight on the seat.

•► Pull over and stop the vehicle safely as soon as possible, paying attention to road and traffic conditions.

•► Engage the parking brake.

•► Switch off the ignition.

•► Open the front-passenger door.

•► Remove the child and the child restraint system from the frontpassenger seat.

•► If necessary, secure the child in a child restraint system on a suitable rear seat.

•► Make sure that there are no objects on the seat adding to the weight.

The system may otherwise detect the additional weight and interpret the seat occupant's weight as greater than it actually is.

•► Keep the seat unoccupied, close the front-passenger door and switch on the ignition.

Observe the multifunction display and check the following: indicator lamp and the multifunction display and check the following:

Seat unoccupied and ignition switched on:

 - the light up and remain lit. When indicator lamp must light up and remain lit. When the indicator lamp is on, OCS has deactivated the front-passenger air bag.

 - the Front Passenger Airbag Enabled See Operator's Manual or Front Passenger Airbag Disabl'd See Operator's Manual display messages must not appear in the multifunction display. Wait for a period of at least 60 seconds until the necessary system checks have been completed and to make sure that the display messages do not appear in the multifunction display.

If these conditions are fulfilled, the front-passenger seat can be occupied again. Whether the indicator lamp remains lit indicator lamp remains lit or goes out depends on how OCS classifies the occupant.

If the conditions are not fulfilled, the system is not operating correctly.

•► Visit a qualified specialist workshop immediately.

WARNING
If the remains off even after performing the above corrective steps, do indicator lamp remains off even after performing the above corrective steps, do not have any children 12 years old and under and other small individuals use the front-passenger seat until the system has been repaired.

Display messages Possible causes/consequences and ► Solutions

Front Passenger Airbag Disabl'd See Operator's Manual

The front-passenger air bag is deactivated during the journey even though an adult or a person larger than a certain size is occupying the front-passenger seat. If additional forces are applied to the seat, the system may interpret the occupant's weight as lower than it actually is.

•► Pull over and stop the vehicle safely as soon as possible, paying attention to road and traffic conditions.

•► Engage the parking brake.

•► Switch off the ignition.

•► Have the occupant get out of the vehicle.

•► Keep the seat unoccupied, close the front-passenger door and switch on the ignition.

Observe the multifunction display and check the following: indicator lamp and the multifunction display and check the following:

Seat unoccupied and ignition switched on:

 - the light up and remain lit. When indicator lamp must light up and remain lit. When the indicator lamp is on, OCS has deactivated the front-passenger air bag.

 - the Front Passenger Airbag Enabled See Operator's Manual or Front Passenger Airbag Disabled See Operator's Manual display messages must not appear in the multifunction display. Wait for a period of at least 60 seconds until the necessary system checks have been completed and to make sure that the display messages do not appear in the multifunction display.

If these conditions are fulfilled, the front-passenger seat can be occupied again. Whether the indicator lamp remains lit indicator lamp remains lit or goes out depends on how OCS classifies the occupant.

If the conditions are not fulfilled, the system is not operating correctly.

•► Visit a qualified specialist workshop immediately.

WARNING
If the remains lit with an adult occupant on the front-passenger seat indicator lamp remains lit with an adult occupant on the front-passenger seat even after performing the above corrective steps, do not have any passenger use the frontpassenger seat until the system has been repaired.

    See also:

    Deactivating the HOLD function
    The HOLD function is deactivated automatically if: • you accelerate and the transmission is in position D or R. • you shift the transmission to position P. • you apply the brakes again with a ...

    Cleaning the display
      Before cleaning the display, make sure that it is switched off and has cooled down.   Clean the display surface using a commercially-available microfiber cloth and TFT/LCD display c ...

    Engine
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