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Humidity sensor ▶
Apply 5 V to terminal No. 1 and 3 on the humidity sensor connector.
Connect the positive (+) probe of a tester on No. 2 terminal and the negative (-) probe on
No. 3 terminal, and measure the output voltage while the voltage is applied.
(output voltage: approx. 0.8 ~ 3.4 V)
Check whether the output voltage is changed when blowing into the inlet of the sensor. I
f
there is a voltage change, the sensor is in normal condition. However, if the voltage is not
changed, replace the humidity sensor.
In addition, if the output voltage is extremely high or low even in the specified range, replace
the humidity sensor. 1.
2.
3.
4.
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5. AIR QUALITY SYSTEM (AQS)
1) Components of AQS
Air Quality System (AQS) changes the air source selection to recirculation mode when polluted
air is detected through AQS sensor. The air source selection returns back to fresh air intake
mode after a specified period or the polluted air is disappeared.
AQS sensor and ambient temperature sensor
AQS sensor
Ambient
temperature
sensor
Connector
AQS and air source selection switch
The AQS switch is integrated with the air source selection switch.
AUTO Mode
The air source is not changed when pressing the AQS and air
source selection switch in “AUTO” mode. However, the
indicator on the switch turned ON/OFF. In other words, the air
source cannot be changed to recirculation mode in AUTO mode
by just pressing the switch. To change the air source to
recirculation mode in AUTO mode, get into Manual mode first,
then press the air source selection switch.
Manual Mode
To change the AQS mode to Manual mode from AUTO mode,
use the MODE switch or the fan speed control dial. In Manual
mode, the “AUTO” symbol on the display is disappeared.
When pressing the AQS and air source selection switch, the
mode is changed in order of AQS LED ON, AQS LED OFF
(fresh air), and air source LED ON (recirculation).
The figure shows that the mode has been changed to the
recirculation mode from fresh air mode under AQS mode (AQS
LED ON) after detecting the polluted outside air.
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2) AQS Operation
The AQS operates under air conditioner AUTO mode or when the AQS switch is pressed under
manual mode. It requires preheating time (for seconds) for operation and the module and
sensor are integrated. (However, it operates only when the DEF (defroster) switch on the ai
r
conditioner switch panel is not pressed in.)
Self diagnosis and preheating process during initial operation of A/C controller
(AUTO mode)
1.
AQS operation (AQS switch is pressed in): detecting the polluted outside air
2.
When the air conditioner controller is operated
in AUTO mode during its initial operation, the
air source is changed to the recirculation
mode and AQS LED comes on.
(This is the self diagnosis and preheating
process for AQS.)
1.
After completing the above process, the
AQS
LED is turned off and the air source is
automatically changed to the fresh air mode.
2.
If the AQS switch is pressed in, the AQS
function works regardless of air conditioner
controller operation.
When pressing the AQS switch, the LED on
the AQS switch is turned on and the
AQS
function is activated.
When the polluted outside air is detected, the
AQS operates and converts the air source to
recirculation mode automatically. At this
moment, the recirculation mode indicato
r
comes on in the display.
1.
2.
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When driving out of polluted area 3.
If the polluted air is disappeared, the air
source is automatically changed to the fresh
air mode and AQS LED stays on.
The air source is not changed when pressing
the AQS and air source selection switch in
“AUTO” mode. To change the air source to
recirculation mode in AUTO mode, get into
Manual mode first, then press the air source
selection switch. 1.
2.
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![SSANGYONG RODIUS 2005 Service Manual 0-20
RODIUS 2005.07
6810-20
AIR CONDITIONING SYSTEM
3) AQS Operation Circuit
1. Ambient temperature switch
2. Sensor ground
3. AQS signal (Output)
4. Ground
5. IGN 2
[AQS sensor] ▶
Measure the volt SSANGYONG RODIUS 2005 Service Manual 0-20
RODIUS 2005.07
6810-20
AIR CONDITIONING SYSTEM
3) AQS Operation Circuit
1. Ambient temperature switch
2. Sensor ground
3. AQS signal (Output)
4. Ground
5. IGN 2
[AQS sensor] ▶
Measure the volt](/manual-img/67/57522/w960_57522-428.png)
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3) AQS Operation Circuit
1. Ambient temperature switch
2. Sensor ground
3. AQS signal (Output)
4. Ground
5. IGN 2
[AQS sensor] ▶
Measure the voltage value of AQS. (between connector terminal No. 3 and 4.)
If the measured voltage is out of 0.1 to 4.8 V, replace the AQS.
If the measured voltage is out of the specified range, replace the AQS. If it is within the
specified range, check as below.
Turn the ignition key to “ON” position.
Measure the voltage between terminal B9 and B15 on the air conditioner controller.
If the voltage value cannot be measured, check the circuit for open. If the measured value is
within the specified range, replace the FATC controller. 1.
2.
3.
4.
5.
6.
Remove the sensor and measure the resistance between terminal No. 5 and 6 on the senso
r
connector. (standard: approx. 25°C, 2.2 kΩ) In addition, if the resistance is extremely
high or low, replace the sensor.
If the measured value is out of the specified range, replace the ambient temperature sensor.
If the measured value is within the specified range, check as below.
Turn the ignition switch to ON position and measure the voltage to ambient temperature
sensor from the FATC controller connector. (standard: approx. 2 V at 25°C)
If the voltage value cannot be measured, check the circuit for open. If the measured value is
within the specified range, replace the FATC controller. 1.
2.
3.
4.[Ambient temperature sensor] ▶
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6. AIR CONDITIONER MODULE SENSORS AND ACTUATORS
1) Duct Temperature Sensor
The duct temperature sensor is installed on the top of heater unit. It detects the inside
temperature of duct and transmits the voltage value that is changed according to resistance
value (NTC) to FATC controller.
(1) Inspection
If the duct temperature sensor defect code (DTC 3) is set, check as below.
▶
Remove the duct temperature sensor and measure the resistance between terminals on the
sensor connector. (standard: approx. 25°C, 2.2 kΩ) In addition, if the resistance is
extremely high or, replace the sensor.
If the measured value is out of the specified range, replace the duct temperature sensor. I
f
the measured value is within the specified range, check as below.
Turn the ignition switch to ON position and measure the voltage to duct temperature senso
r
from the FATC controller connector.
(standard: approx. 2 V at 25°C)
If the voltage value cannot be measured, check the circuit for open. If the measured value is
within the specified range, replace the FATC controller.
1.
2.
3.
4.
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2) Power Transistor
The power transistor controls the fan speed. It controls the blower motor operating speed
without stages by changing the current value to the base of power transistor when receiving the
fan control signal from FATC.
Front air conditioner power transistor
Rear air conditioner power transistor
(1) Inspection
If the power transistor defect code (DTC 6) is appeared, check as below.
▶
Turn the ignition switch to ON position.
Measure the voltage between terminals while changing the fan speed from stage 1 to stage
6
The specified voltage value in each stage:
1.
2.
3.
If the voltage is out of specified value, check the circuit for open. If the circuit is in normal
condition, replace the power transistor.
4.
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3) Mode Door Actuator
The mode door actuator is an actuator that closes, opens and adjusts the mode door for VENT,
FLOOR and DEF mode to change the air flow directions according to FATC controller. Unde
r
the FATC controller AUTO mode, it stays on DEF mode until the engine coolant temperature
reaches at normal operating level and the mode is changed as below when the MODE switch is
pressed.