BMW X3 xDrive20i 2013 Owner's Handbook Manual page 145

Runflat indicator
Reinitialise the runflat indicator after a trailer has
been attached or detached or the inflation pres‐
sure has been corrected.
Exterior mirrors
Two exterior mirrors which bring both rear cor‐
ners of the trailer into your field of view are re‐
quired by law. Mirrors of this kind can be ob‐
tained from your Service centre as optional
accessories.
Power consumption
The power output of the trailer's rear lights must
not exceed the following values:
▷ Turn indicators: 42 Watts per side
▷ Rear lights: 60 Watts per side
▷ Brake lights: 84 Watts total
▷ Rear fog lights: 42 Watts total
▷ Reversing lights: 42 Watts total
Keep the switch-on times of the current con‐
sumer units in the caravan mode short in order
not to place an excessive load on the vehicle
battery.
Function of the rear lights
Before beginning your journey, check the
function of the rear lights of the trailer, as other‐
wise this might endanger other road users.◀
Towing a trailer
Notes
Appropriate speed when towing a trailer
Keep to an appropriate speed when tow‐
ing a trailer. Speeds in excess of approximately
80 km/h, 50 mph can be enough to produce a
swaying or fishtailing motion, depending on the
design of the trailer and the load it is carrying.◀
Online Edition for Part no. 01 40 2 900 867 - 03 12 490
Towing a trailer
Maximum speed when towing a trailer
If you are towing a trailer, increase tyre
pressures by 0.2 bar all round and do not exceed
a top speed of 100 km/h / 60 mph, as the higher
axle load could result in damage to the tyres if
the car is driven at higher speeds. Note the max‐
imum possible tyre pressures stated on the
tyres.◀
Counteracting snaking
If the trailer begins to snake, the vehicle combi‐
nation can only be stabilised by braking hard im‐
mediately.
Make sure that the necessary steering correc‐
tions are carried out as cautiously as possible,
taking other road users into consideration.
Uphill gradients
In the interest of safety and to avoid holding up
other traffic, do not attempt to climb gradients
steeper than 12 % when towing a trailer.
If higher trailer loads are permitted later, the limit
is 8 %.
Downhill gradients
On downward inclines, a vehicle combination
has tendency to snake at an earlier stage.
Before the downward incline, shift down to the
next-lowest gear and drive downwards slowly.
High loads and high outside
temperature
Long journeys with a high load and outside
temperature
On long journeys with a high trailer load and high
outside temperature, make sure that the fuel
tank is more than 1/4 full, as otherwise the en‐
gine output can decrease or engine damage can
occur.◀
Driving hints
145