Trailer stabilisation systemTrailer stabilisation system  - Driving the vehicle with a trailer or caravan - Towing a trailer - Driving tips - Audi A4 Owner's Manual - Audi A4

Trailer stabilisation helps to reduce the risk of the vehicle skidding when towing a trailer.

The trailer stabilisation system is operational only when the ESP is switched on and there is no malfunction in the ESP.

When is the trailer stabilisation system activated?

Trailer stabilisation is active when the following requirements are met:

  • The ESP must NOT be switched off,
  • The trailer connector must be properly secured in the vehicle socket.
  • Vehicle speed must be higher than approx. 60 km/h.

How trailer stabilisation works:

In many cases, the driver can stabilise a swaying trailer by manually braking the vehicle.

However, if the ESP detects that the trailer is swaying and this is affecting the towing vehicle, it will automatically brake the vehicle to stabilise the trailer by slowing it down. The warning lamp ö will light up in the instrument cluster. If possible, do not turn the steering wheel at this stage.

In order to warn traffic behind you, the brake lights will come on during this automatic braking operation.

A trailer weighing less than 70% of the kerb weight of the towing vehicle may sway quite considerably without the trailer stabilisation system intervening. This can happen when the swaying movements of the light-weight trailer are not or hardly passed on to the towing vehicle and are therefore not detected by the ESP.

If the system for activating the trailer brake lights is defective, this will be indicated in the instrument cluster display, Bulb monitor Requirements for correct functioning of the trailer stabilisation system.

Requirements for correct functioning of the trailer stabilisation system

If these conditions are not met in full, the trailer stabilisation system will only intervene to a limited extent or not at all ⇒. .

  • The electrical connection between the towing vehicle and the trailer must be functioning correctly, without any defects.
  • The load on the trailer must be properly secured.
  • The tyre pressures on both the vehicle and the trailer must be adapted to the load that is being carried.
  • Where possible, operate the trailer with the maximum permitted draw bar weight.
  • The trailer overrun brake must be set correctly. This is important to ensure that the trailer can be braked correctly, to avoid the vehicle and trailer jack-knifing and to prevent excess braking of the trailer.
  • At low outside temperatures, both the towing vehicle and the trailer should be fitted with winter tyres.

It is essential that you adjust your speed to suit the weather, road and WARNING

It is essential that you adjust your speed to suit the weather, road and traffic conditions. Do not let the trailer stabilisation system tempt you into taking any risks when driving this can cause accidents.

  • The ESP and trailer stabilisation system cannot defy the laws of physics. This should be kept in mind, particularly on slippery and wet roads and when towing a trailer with a light load.
  • The trailer stabilisation system is functional, regardless of whether the trailer has a mechanical overrun brake or not.
  • The trailer stabilisation system is not always able to detect swaying of trailers with a light load and will therefore not intervene.
  • A trailer can still jack-knife on slippery roads with little grip, even if the towing vehicle is equipped with the trailer stabilisation system.
  • Trailers with a high centre of gravity may even tip over before they start to sway sideways.
  • If you are not towing a trailer, but the trailer socket is being used (e.g. for an illuminated bicycle rack), the trailer stabilisation system may be activated in extreme driving conditions. Please note the additional information and warnings