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HVAC
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5. COMPONENTS OF HVAC
A. CONTROL PANEL
NOTE
The removal and installation of all components are
covered in “On Vehicle Repairs” in this section.
MANUAL HVAC CONTROL PANEL
ROTARY KNOBS
A Air Distribution Control
B Blower Speed Control
C Temperature Selection
PUSH BUTTONS
D Fresh / Recirculation Air Mode
E AC On / Off
The HVAC control panel consists of 3 rotary knobs &
2 Push buttons that can be used to set the required
temperature inside the cabin. In addition to this the
control panel also acts as a control unit for the HVAC
system in which all the software calibrations are em-
bedded.
i) AIR DISTRIBUTION CONTROL
The mode knob is used to select the air delivery
mode. There are 5 different modes as given below.
Chest Mode
Chest – Leg Mode
Leg Mode
Leg – Defrost Mode*
Defrost Mode*
NOTE
When the Leg- defrosts or defrost mode is selected,
the HVAC control unit will select the recommended
settings for best performance of the selected func-
tion. These settings can be overridden by manual
intervention.
(For details, refer HVAC layout and
working).
ii) BLOWER SPEED CONTROL
The Fan speed selector allows the user to select four
blower speeds – LO, M1, M2 and HI. An OFF posi-
tion is also provided to shut the system off.
iii) TEMPERATURE SELECTION
The temperature selector knob can be used to select
the required temperature varying from full cold
(on
the extreme anti-clockwise)
and full hot
(on the ex-
treme clockwise)
.
iv) FRESH / RECIRCULATION AIR
This push button can be used to position the Air inlet
door, either to allow fresh air to come inside the cab-
in or to recirculate the air within the cabin.
v) AC ON / OFF
The air-conditioning ON / OFF switch is located on
the control panel. Press the switch to decrease the
air temperature inside the cabin. The indicator lamp
on the switch glows when the switch is in “ON” posi-
tion. The blower motor must be running for the
indicator lamp to glow.
When it is pressed once AC ON
(Amber LED glows)
is selected and if pressed again AC switches OFF.
This is also helpful to defrost / defog the windshield
in case of high air humidity.