CITROEN DS3 Owner's Handbook Manual page 230

Cooling
Towing a trailer on a slope increases the
temperature of the coolant.
As the fan is electrically controlled, its cooling
capacity is not dependent on the engine speed.
To lower the engine speed, reduce your
speed.
The maximum towed load on a long incline
depends on the gradient and the ambient
temperature.
In all cases, keep a check on the coolant
temperature.
If the warning lamp and the
STOP warning lamp come on,
stop the vehicle and switch off
the engine as soon as possible.
Braking
Towing a trailer increases the braking distance.
Tyres
Check the tyre pressures of the towing
vehicle and of the trailer, observing the
recommended pressures.
Lighting
Check the electrical lighting and signalling
on the trailer.
The rear parking sensors will be
deactivated automatically if a genuine
CITROËN towbar is used.
RACING towbar
Your vehicle cannot be fitted with a
towbar. The space occupied by the
sport diffuser prevents this.