Safety systems

WARNING

Driving with the brake warning lamp illuminated can result in an accident. Have your brake system checked immediately if the brake warning lamp stays on. 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
The red brake system warning lamp comes on while the engine is running. A warning tone also sounds.

The red brake system warning lamp comes on while the engine is running. A warning tone also sounds.

Risk of accident

There is not enough brake fluid in the brake fluid reservoir.

  • 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 immediately.
  • Observe the additional display messages in the multifunction display.

Do not add brake fluid. This will not correct the malfunction.

ABS warning lamp is lit while the engine is running.

The yellow ABS warning lamp is lit while the engine is running.

Risk of accident

ABS (Anti-lock Brake System) is deactivated due to a malfunction. ESP (Electronic Stability Program), BAS (Brake Assist), hill start assist and ESP trailer stabilization, for example, are therefore also deactivated, for example.

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

  • Observe the additional display messages in the multifunction display.
  • Drive on carefully.
  • Visit a qualified specialist workshop.

If the ABS control unit is faulty, there is also a possibility that other systems, such as the navigation system or the automatic transmission, will not be available.

ABS warning lamp is lit while the engine is running.

The yellow ABS warning lamp is lit while the engine is running.

Risk of accident

ABS is temporarily unavailable. ESP, BAS, EBD (electronic brake force distribution), hill start assist and ESP trailer stabilization, for example, are therefore also unavailable.

Self diagnosis is not yet complete.

For example, the on-board voltage may be insufficient. The brake system continues to function normally, but without the functions listed above. The wheels could therefore lock if you brake hard, for example.

  • Carefully drive a suitable distance making slight steering movements at a speed above 12 mph (20 km/h). The functions mentioned above are available again when the warning lamp goes out.

If the warning lamp is still on:

  • Observe the additional display messages in the multifunction display.
  • Drive on carefully.
  • Visit a qualified specialist workshop.
ABS warning lamp is lit while the engine is running. A warning tone also

The yellow ABS warning lamp is lit while the engine is running. A warning tone also sounds.

Risk of accident

EBD is faulty. Therefore, ABS, BAS, hill start assist and ESP trailer stabilization, for example, are also not available due to a malfunction.

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

  • Observe the additional display messages in the multifunction display.
  • Drive on carefully.
  • Visit a qualified specialist workshop.

The red brake warning lamp, the yellow ESP and ESP OFF warning lamps

The red brake warning lamp, the yellow ESP and ESP OFF warning lamps and the yellow ABS warning lamp are lit while the engine is running.

Risk of accident

ABS and ESP are faulty. Therefore, BAS, EBD, hill start assist and ESP trailer stabilization, for example, are also not available due to a malfunction.

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

  • Observe the additional display messages in the multifunction display.
  • Drive on carefully.
  • Visit a qualified specialist workshop.
ESP warning lamp flashes while the vehicle is in motion.

The yellow ESP warning lamp flashes while the vehicle is in motion.

Risk of accident

ESP or traction control has intervened because there is a risk of skidding or at least one wheel has started to spin. Cruise control is deactivated.

  • Only depress the accelerator pedal as far as necessary when pulling away.
  • Release the accelerator pedal while the vehicle is in motion.
  • Adapt your driving style to suit the road and weather conditions.
  • Do not deactivate ESP.

For exceptions: ().

ESP warning lamp flashes while the vehicle is in motion.

The yellow ESP warning lamp flashes while the vehicle is in motion.

At least one wheel is spinning and the electronic traction system is deactivated to prevent the brakes on the drive wheels from overheating.
  • Observe the additional display messages in the multifunction display.

The electronic traction system switches back on again as soon as the brakes have cooled down. The display message disappears and the   warning lamp goes out.

ESP OFF warning lamp is lit while the engine is running.

The yellow ESP OFF warning lamp is lit while the engine is running.

Risk of accident

ESP and ESP trailer stabilization are deactivated. ESP will not stabilize the vehicle if it starts to skid or if a wheel starts to spin.

  • Reactivate ESP. For exceptions: ().
  • Adapt your driving style to suit the road and weather conditions.

If ESP cannot be activated:

  • Have ESP checked at a qualified specialist workshop.
The yellow ESP and ESP OFF warning lamps are lit while the engine is running.The yellow ESP and ESP OFF warning lamps are lit while the engine is running.

The yellow ESP and ESP OFF warning lamps are lit while the engine is running.

Risk of accident

ESP, BAS, hill start assist and ESP trailer stabilization are not available due to a malfunction. ESP will not stabilize the vehicle if it starts to skid or if a wheel starts to spin.

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

  • Observe the additional display messages in the multifunction display.
  • Drive on carefully.
  • Visit a qualified specialist workshop.
The yellow ESP and ESP OFF warning lamps are lit while the engine is running.The yellow ESP and ESP OFF warning lamps are lit while the engine is running.

The yellow ESP and ESP OFF warning lamps are lit while the engine is running.

Risk of accident

ESP, BAS, hill start assist and ESP trailer stabilization are temporarily unavailable.

ESP is temporarily unavailable. ESP will not stabilize the vehicle if it starts to skid or if a wheel starts to spin. Self diagnosis is not yet complete.

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

  • Carefully drive a suitable distance making slight steering movements at a speed above 12 mph (20 km/h). The functions mentioned above are available again when the warning lamp goes out.

If the warning lamp is still on:

  • Observe the additional display messages in the multifunction display.
  • Drive on carefully.
  • Visit a qualified specialist workshop.
The red brake system warning lamp comes on while the vehicle is moving. A warning tone also sounds.

The red brake system warning lamp comes on while the vehicle is moving. A warning tone also sounds.

You are driving with the parking brake applied.
  • Release the parking brake The warning lamp goes out and the warning tone ceases.
SRS warning lamp is lit while the engine is running.

The red SRS warning lamp is lit while the engine is running.

Risk of injury

The restraint systems are malfunctioning. The air bags or ETDs may either be triggered unintentionally or, in the event of an accident, not be triggered at all.

  • Drive on carefully.
  • Visit a qualified specialist workshop immediately.
    See also:

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