AIR CONDITIONING
DESCRIPTION AND OPERATION 82-13
The control panel switches are all non-latching pushswitches except for the LH and RH temperature switches, which
are centre-off rocker switches. The switches have the following functions:
LH and RH temperature switches. Enabled only while the system is on:
lEach press increases or decreases the related temperature setting, in steps of 1 °C (2 °F), between 16 and 28
°C (60 and 84 °F).
lIf the decrease side of the switch is pressed when a temperature of 16 °C (60 °F) is set, the display changes to
LO (maximum cold).
lIf the increase side of the switch is pressed when a temperature of 28 °C (84 °F) is set, the display changes to
HI (maximum hot).
lIf a switch is kept depressed, step changes occur every 0.4 seconds.
A/C on/off switch. Switches the system on and off. When used to switch the system on, the system resumes the
configuration in use prior to the previous off selection.
Blower switch. Enabled only while the system is on. Provides manual control of blower speed:
lEach press changes the blower speed, in sequence, through off (only available if economy mode is selected on)
and five incremental speeds.
lIf the switch is kept depressed, after 1 second subsequent speed increments occur every 0.4 second until blower
reaches high speed. Releasing and then pressing the switch again changes blower back to off or low speed.
Distribution switch. Enabled only while the system is on. Provides manual control of air distribution:
lEach press changes the air distribution, in sequence, through footwells only, footwells and windscreen/side
windows demist, windscreen/side windows demist only, face level only, face level and footwells.
lIf the switch is kept depressed, after 1 second subsequent distribution changes occur every 0.4 seconds until
distribution reaches face level and footwells. Releasing and then pressing the switch again changes distribution
back to footwells only.
External air temperature (EXT) switch. Enabled while the system is on or off. Switches the external temperature output
on and off:
lIf the system is already on, the temperature output overrides the system outputs for approximately 7 seconds,
then the display reverts to system outputs.
lIf the system is switched on while the external temperature output is on, the system outputs override the external
temperature output.
Fresh/Recirculated air switch. Enabled only while the system is on. Provides manual control of inlet air selection.
Defrost mode switch. Starts the system in, or switches the system to and from, defrost mode.
Automatic mode (AUTO) switch. Starts the system in, or switches the system to and from, the automatic mode.
Economy mode (ECON) switch. Enabled only while the system is on. Provides manual on/off control of the refrigerant
system compressor, to reduce fuel consumption when there is no requirement for cool or dehumidified air, e.g. when
the ambient temperature is lower than the LH and RH temperature settings.
Temperature settings: The LH and RH temperature settings are reference inputs used by the control system and give
an approximation of the temperatures that will be established in the cabin. They are not necessarily actual distribution
outlet temperatures, or the temperatures at specific points in the cabin.
Audible warning: A 'beep' is emitted from the ATC ECU each time it receives a control switch input. This audible
warning can be switched off and on by pressing and holding the AUTO switch, then pressing and holding the A/C on/
off switch until the audible warning sounds (approximately 3 seconds). While switched off, the audible warning still
sounds when:
lSwitching between °F and °C on the display.
lSwitching the audible warning from off to on.
lSwitching the timed feet function on and off.
lSwitching the timed recirculated inlet air on and off.
lSwitching the latched recirculated inlet air on and off.
lWhen there is a fault warning.
lRunning the self diagnostic routine.
