Audi R8 2008 Service Training Manual page 59

Climatronic Control Module J255
The setpoint for the temperature flap is set using the
"Temperature" rotary knob. The rotary knob is infinitely
variable and activates the "Maximum Cool" function in
the lowest setting and the "Maximum Heat" function in
the highest setting.
Automatic mode of the air conditioning system can
be deactivated with the "Air Flow" or "Air Distribution"
rotary knob or by pressing the DEFROST or AC button.
The air conditioner compressor can be switched ON
or OFF by pressing the AC button. The system is active
without cooling function when the air conditioner
compressor is OFF.
Defrost
Temperature
Function Key
Rotary Knob
Left Seat Heater
Function Key
Function Key
The seat heater is optional equipment with the Audi R8.
The three heater settings can be set by pressing the
function keys.
In setting 0 the seat heater is OFF. Setting 0 cannot
be selected directly from setting 3 — it can only be
activated by pressing the "Minus" key several times.
The function keys are backlit, with currently "active"
functions indicated by integrated LEDs. Instrument
Cluster Control Module J285 provides the dimming
signals terminal 58d for the function LEDs and terminal
58s for the key backlighting through the CAN bus.
The LEDs of the function buttons and the button
backlighting cannot be switched individually.
Air Flow
Rotary Knob
Air Recirculation
Function Key
AUTO
Air Conditioning
Rear Window
Air
Defroster
Distribution
Function Key
Rotary Knob
Right Seat
Heater Function
Key
AC Function Key
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