User's Manual

Heating and cooling 111
Controls Safety Driving tips General maintenance Self-help Technical data
Auxiliary heating and auxiliary
ventilation
Applies to vehicles: with auxiliary heating - under development at the time of printing
Description
The auxiliary heating and ventilation systems heat and
cool the interior independently of the engine.
The auxiliary heating  works in conjunction with the air condi-
tioner system, but does not rely on heat from the engine. Instead of
this, the system burns fuel. The system's main function is to warm
up the interior of the vehicle and to defrost the windows in cold
weather.
The auxiliary heating system can be used both when the vehicle is
stationary and when driving (to provide extra heat while the engine
is warming up).
The auxiliary ventilation  also operates independently of the
engine. This feature can be used to cool the interior with the blower
when the vehicle is left parked in the sun.
The system will automatically activate either the auxiliary heating or
the auxiliary ventilation mode, depending on the actual tempera-
ture measured inside the car and the temperature you have set with
the air conditioner controls. It is possible to alter the temperature
setting while the auxiliary heating/ventilation is running.
Switching on and off
There are two different ways of switching on the auxiliary
heating/ventilation system.
• Immediate start: You can switch the auxiliary heating/ventilation
on and off at any time in the MMI Car menu ⇒ page 112. You can
also switch the system on and off using the remote control
⇒ page 114.
• Switching on via timer: You can programme various start times
using the timers ⇒ page 112. However you must first activate the
timer before the auxiliary heating/ventilation system will switch on
automatically.
The auxiliary heating/ventilation will switch itself off at the end of
the programmed running time. The running time can be set to 15,
30, 45 or 60 minutes ⇒ page 113.
WARNING
• The auxiliary heating must not be allowed to run when the
vehicle is in a confined space because it can give off toxic fumes.
• To avoid any possible fire risk, never have the auxiliary heating
switched on when refuelling the vehicle.
• Because of the high temperatures which occur when the auxil-
iary heating is running, make sure when parking the car that the
exhaust outlet under the car is not obstructed in any way and that
the exhaust gases do not come into contact with flammable mate-
rials (fire risk).
Note
• It is advisable to open the air outlets when using the auxiliary
heating/ventilation.
• The auxiliary heating/ventilation will not switch on if the fuel in
the tank has reached the reserve zone.
• The auxiliary heating/ventilation will not switch on if the battery
charge level is low.
• The symbols  (auxiliary ventilation) or  (auxiliary heating)
flash in the instrument cluster next to the clock display when the
auxiliary heating/ventilation is switched on. Both symbols light
continuously when the timer is activated.
• At low outside temperatures some visible water vapour may
form in the engine compartment. This is a normal phenomenon,
and no reason for concern.
document_0900452a8179700c.book Seite 111 Donnerstag, 22. März 2007 10:19 10