Mercedes-Benz SLR McLaren. Operator's Manual.

Controls in detail
Automatic climate control
Residual heat and ventilation
With the engine switched off, it is possible
to continue to heat or ventilate the interior
for up to 30 minutes. This feature makes
use of the residual heat produced by the
engine.
190
i
How long the system will provide heating
depends on the coolant temperature
and the temperature set by the
operator. The blower will run at speed
setting 1 regardless of the air distribution
control setting.
Activating
Turn the SmartKey in the starter switch
to position 1 or 0 or remove it from the
starter switch.
Press button T ( page 184).
The indicator lamp on button T
comes on.
Deactivating
Press button T ( page 184).
The indicator lamp on button T
goes out.
The residual heat is automatically turned
off:
when the ignition is switched on
after about 30 minutes
if the battery voltage drops