Heating, Ventilation & Air Conditioning: Overview Hyundai Azera I

OIL RETURN OPERATION

There is close affinity between the oil and the refrigerant. During normal operation, part of the oil recirculates with the refrigerant in the system. When checking the amount of oil in the system, or replacing any component of the system, the compressor must be run in advance for oil return operation. The procedure is as follows

1. Open all the doors and the engine hood.
2. Start the engine and air conditioning switch to "ON" and set the blower motor control knob at its highest position.
3. Run the compressor for more than 20 minutes between 800 and 1,000 RPM in order to operate the system.
4. Stop the engine.

DESCRIPTION

A/C pressure transducer convert the pressure value of high pressure line into voltage value after measure it. By converted voltage value, engine ECU controls cooling fan by operating it high speed or low speed. Engine ECU stop the operation of compressor when the temperature of refrigerant line is so high or so low irregularly to optimize air conditioning system.

Scheme 17

1. Measure the pressure of high pressure line by measuring voltage output between No.1 and No.2 terminals.
2. Inspect the voltage value whether it is sufficient to be regular value or not. Voltage = 0100878835* Pressure + 0.5[kgf/cm 2 ]
3. If the measured voltage value is not specification, replace the A/C pressure transducer. Error range: ± 2.5%

Scheme 18

1. Disconnect the negative (-) battery terminal
2. Disconnect A/C pressure transducer connector (3P) from wiring harness. NOTE: Take care that liquid suction pipe is not bent.
3. Installation is the reverse order of removal.

Scheme 19

The evaporator temperature sensor will detect the evaporator core temperature and interrupt compressor relay power in order to prevent evaporator freezing by excessive cooling.

It is a negative type thermistor whose resistance is inversely proportional to temperature.

1. Heater unit includes mode control actuator and temperature control actuator.
2. Temperature control actuator is located at the heater unit. It regulates the temperature by the procedure as follows. Signal from control unit adjusts position of temperature door by operating temperature switch and then temperature will be regulated by the hot/cold air ratio decided by position of temperature door.

Scheme 20

1. Verify the temperature control actuator operates to the hot position when connecting 12V to the terminal 3 and grounding terminal 4. Verify that the temperature control actuator operates to the cool position when connecting in the reverse.
2. Check the voltage between terminals 5 and 6. VOLTAGE SPECIFICATION Door position Voltage (5-6) Error detecting Max. cooling 0.3 ± 0.15V Low voltage: 0.1V or less Max. heating 4.7 ± 0.15V High voltage: 4.9V or more It will feedback current position of actuator to controls.

The mode control actuator is located at the heater unit. It adjusts position of mode door by operating mode control actuator based on signal of A/C control unit. Pressing mode select switch makes the mode control actuator shift in order of vent --> B/L --> floor --> mix.

Scheme 21

1. Verify that the mode control actuator operates to the defrost position when connecting 12V to the terminal 3 and grounding terminal. Verify that the mode control actuator operates to the vent position when connecting in the reverse.
2. Check the voltage between terminals 5 and 6. VOLTAGE SPECIFICATION Door position Voltage (5-6) Error detecting Vent 0.3 ± 0.15V Low voltage: 0.1V or less Defrost 4.7 ± 0.15V High voltage: 4.9V or more * It will feedback current position of actuator to controls.

Scheme 22

1. Disconnect the negative (-) battery terminal.
2. Remove the driver' s crush pad lower panel. (Refer to «INTERIOR»(ref-287152) )
3. Disconnect the mode control actuator connector (A) after removing the air duct.
4. Loosen the mounting screws and then remove the mode control actuator (B).
5. Installation is the reverse order of removal.

Scheme 23

Scheme 24

1. In-car air temperature sensor is located at the center facia panel.
2. The sensor contains a thermistor which measures the temperature of the inside. The signal decided by the resistance value which changes in accordance with perceived inside temperature, is delivered to heater control unit and according to this signal the control unit regulates in car temperature to intended value.
3. It perceives the inside temperature, changes the resistance value, and enters the corresponding voltage into the automatic temperature control module.
4. It will used for discharge temperature control, sensor fail-safe, temperature door control, blower motor level control, and A/C auto control.

Scheme 25

1. Ignition "OFF".
2. Remove the in car sensor connector.
3. Blow air with changing temperature to the in car sensor air inlet. Measure sensor resistance between 2 and 4 terminals.
4. In car sensor is negative type thermistor that resistance will rise with lower temperature, and reduce with higher temperature. TEMPERATURE SPECIFICATION Temperature [°C (°F)] Terminals 2 and 4 (kohms) 50 (122) 10.81 ± 2.2% 35 (95) 19.57 ± 1.6% 25 (77) 30.00 ± 1.20% 15 (59) 47.13 ± 1.7% 0 (32) 97.71 ± 2.4% -15 (-74.2) 216.1 ± 3.2% NOTE: In car sensor is negative type thermistor that resistance will rise with lower temperature, and reduce with higher temperature.

Scheme 26

1. Disconnect the negative (-) battery terminal.
2. Remove the center facia panel. (Refer to «INTERIOR»(ref-287152) ).
3. Loosen the mounting 2 screws and then remove the in-car sensor (A).
4. Installation is the reverse order of removal.

Scheme 27

1. The photo sensor (B) is located at the left side of defrost nozzle.
2. The photo sensor contains a photovoltaic (sensitive to sunlight) diode. The solar radiation received by its light receiving portion, generates an electromotive force in proportion to the amount of radiation received which is transferred to the automatic temperature control module so that the solar radiation compensation will be performed.

1. A.Q.S is located at center support in front of the engine radiator, and detects hazardous elements in ambient air providing output signal to control.
2. It will detect sulfurous acid gas, carbon dioxide, carbon monoxide, hydrocarbon and allergen.

This has particle filter which eliminates foreign materials and odor. The particle filter includes odor filter as well as conventional dust filter to ensure comfortable interior environment.

Scheme 28

Scheme 29

Scheme 30

1. Open the glove box (B). Lower the glove box down completely by removing the glove box stopper (A) to the glove box.
2. Remove the damper from glove box.
3. Remove the filter cover (A) with pushing the knob.
4. Replace the air filter (B), install it after making sure of the direction of air filter. NOTE: In case of driving in an air-polluted area or rugged terrain, check and replace the air filter as frequently as possible. Replacement period: 15,000 km (9320 mile)

Scheme 31

1. The intake actuator is located at the blower unit.
2. It regulates the intake door by signal from control unit.
3. Pressing the intake selection switch will shift between recirculation and fresh air modes.

GENERAL DESCRIPTION

A water temp, sensor located at heater unit, detects coolant temperature. Its signal is used for cold engine lockout control. When the driver operates the heater before the engine is warmed up, the signal from sensor causes the heater control unit to reduce blower motor speed until coolant temperature reaches the threshold value.

DTC DESCRIPTION

The A/C controller sets DTC B1202 if there is an open circuit in water temp, sensor signal harness or the measured resistance value of the sensor is more than the threshold value (about 176.3 kohms)

Refer to DTC B1202 .

The A/C controller sets DTC B1203 if there is a short circuit in water temp, sensor signal harness or the measured resistance value of sensor is less than threshold value (about 1.2 kohms)

Temperature control actuator located at heater unit, regulates the temperature by the procedure as follows. Signal from control unit adjusts position of temp, door by operating temp, motor and then temperature will be regulated by the hot/cold air ratio decided by position of temp. door.

The A/C controller sets DTC B1204 if there is an open circuit or poor connection in the air mix potentiometer.

Refer to DTC B1204 .

The A/C controller sets DTC B1205 if there is a short to power in the air mix potentiometer.

Intake door located at heater unit controls the inlet of car. When driver operates the intake switch, A/C controller recirculation receives mode signal from intake switch and operates intake door actuator to turn intake door to intended position, (with fresh mode signal, intake door is closed and with fresh mode signal, intake door is opened).

The A/C controller sets DTC B1208 if there is an open circuit or poor connection in the intake potentiometer.

Intake door located at heater unit controls the inlet of car. When driver operates the intake switch, A/C controller recirculation receives mode signal from intake switch and operates intake door actuator to turn intake door to intended position, (with fresh mode signal, intake door is closed and with fresh mode signal, intake door is opened).

The A/C controller sets DTC B1209 if there is a short to power in the Intake potentiometer.

The in car temperature sensor located at crush pad, control unit contains a thermistor which measures the temperature of the inside. The signal, decided by the resistance value which changes in accordance with perceived inside temperature, is delivered to heater control unit and according to this signal, the control unit regulates in car temperature to intended value.

The A/C controller sets DTC B1233 if there is a short circuit in car temp, sensor signal harness or the measured resistance value of sensor is less than threshold value (about 7.46 kohms)

Refer to DTC B1233 .

The A/C controller sets DTC B1234 if there is an open circuit in car temp, sensor signal harness or the measured resistance value of sensor is more than threshold value (about 509.57 kohms)

The ambient temperature senor located at the center stay of the condenser, detects ambient air temperature. It is a negative type thermistor whose resistance is inversely proportional to temperature. Its output is used for discharge temperature sensor, sensor fail-safe, temperature regulation door lock, blower motor level control, mix mode control and in-car humidity control.

The A/C controller sets DTC B1237 if there is a short circuit in ambient temp, sensor signal harness or the measured resistance value of sensor is less than threshold value (about 7.48 kohms)

Refer to DTC B1237 .

The A/C controller sets DTC B1238 if there is an open circuit in ambient temp, sensor signal harness or the measured resistance value of sensor is more than threshold value (about 527 kohms)

The Evaporator temperature sensor located on heater unit, detects the core temperature and interrupts compressor relay power, in order to prevent evaporator freezing by excessive cooling. It is a negative type thermistor whose resistance is inversely proportional to temperature.

The A/C controller sets DTC B1241 if there is a short circuit in evaporator temp, sensor signal harness or the measured resistance value of sensor is less than threshold value (about 0.9 kohms)

Refer to DTC B1241 .

The A/C controller sets DTC B1242 if there is an open circuit in evaporator temp, sensor signal harness or the measured resistance value of sensor is more than threshold value (about 13.6 kohms)

Temperature control actuator located at heater unit, regulates the temperature by the procedure as follows. Signal from control unit adjusts position of temp, door by operating temp, motor and then temperature will be regulated by the hot/cold air ratio decided by position of temp. door.

The A/C controller sets DTC B1245 if there is an open circuit or poor connection in the air mix potentiometer.

Refer to DTC B1245 .

The A/C controller sets DTC B1246 if there is a short to power in the air mix potentiometer.

The mode control actuator mounted on heater unit, adjusts position of mode door by operating Direction Motor based on signal of A/C control unit. Pressing mode select switch makes the mode control actuator shift in order of vent --> B/L --> floor --> mix.

The A/C controller sets DTC B1249 if there is an open circuit or poor connection in the Direction potentiometer.

Refer to DTC B1249 .

The A/C controller sets DTC B1250 if there is a short to power in the Direction potentiometer.

AQS (Air Quality System) keeps air inside in the most suitable state for driver. In polluted area AQS detects hazardous gas and intercepts inflow automatically, Inversely, In fresh area it allows the inflow of air to prevent the shortage of air and the accumulation of carbon dioxide. AQS sensor is located at front side of condenser and once hazardous gas is detected, it delivers the voltage signal to A/C controller for closing intake door.

The A/C controller sets DTC B1257 if there is an open circuit in AQS sensor signal harness or the measured voltage value of sensor is more than threshold value.

Refer to DTC B1257 .

The A/C controller sets DTC B1258 if there is a short circuit in AQS sensor signal harness or the measured voltage value of the sensor is less than the threshold value.

AQS (Air Quality System) keeps air inside in the most suitable state for driver. In polluted area AQS detects hazardous gas and intercepts inflow automatically, Inversely, In fresh area it allows the inflow of air to prevent the shortage of air and the accumulation of carbon dioxide. AQS sensor is located at front side of condenser and once hazardous gas is detected, it delivers the voltage signal to A/C controller for closing intake door.

The A/C controller sets DTC B1259 if preheating time of AQS sensor is over 40 sec. or signal from AQS sensor is not within specifications.

Temperature control actuator located at heater unit, regulates the temperature by the procedure as follows. Signal from control unit adjusts position of temp, door by operating temp, motor and then temperature will be regulated by the hot/cold air ratio decided by position of temp. door.

The A/C controller sets DTC B2406 if the air mix actuator doesn't move to intended position within 40 sec. (In this case, A/C controller try to move temp, door for 2 sec. 3 times, every 20 sec. before setting DTC).

Intake door located at heater unit controls the inlet of car. When driver operates the intake switch, A/C controller recirculation receives mode signal from intake switch and operates intake door actuator to turn intake door to intended position, (with fresh mode signal, intake door is closed and with fresh mode signal, intake door is opened.

The A/C controller sets DTC B2408 if the intake motor Doesn't move to intended position within 40 sec. (The A/C controller attempts to move the intake door for a 2 second duration at a frequency of 3 times every 20 seconds before storing a DTC.)

The mode control actuator mounted on heater unit, adjusts position of mode door by operating Direction Motor based on signal of A/C control unit. Pressing mode select switch makes the mode control actuator shift in order of vent --> B/L --> floor --> mix.

The A/C controller sets DTC B2409 if the direction motor doesn't move to intended position within 40 sec. (In this case, A/C controller try to move mode door for 2 sec. 3 times, every 20 sec. before setting DTC).