Air Conditioning System: Overview Kia Rio III

Oil Return Operation

There is close affinity between the oil and the refrigerant.

During normal operation, part of the oil recirculation 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

The compressor is the power unit of the A/C system.

It is located on the side of engine block and driven by a V-belt of engine.

The compressor changes the low pressure and low temperature refrigerant gas into the high pressure and high temperature refrigerant gas.

The A/C Pressure Transducer (APT) 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.

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1. Measure the pressure of high pressure line by measuring voltage output between terminal "1" and "2".
2. Inspect the voltage value whether it is sufficient to be regular value or not.
3. If the measured voltage value is not within specification, replace the A/C pressure transducer.

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1. Disconnect the negative (-) battery terminal.
2. Recover the refrigerant with a recovery/charging station.
3. Disconnect the A/C pressure transducer connector (A).
4. Remove the A/C pressure transducer (A). Tightening torque: 10~12 N.m (1.02~1.22 kgf.m, 7.4~8.8 lb-ft) CAUTION: Take care that liquid & suction pipe are not bent.
5. Install in the reverse order of removal. NOTE: When installing, replace with new O-ring (A).

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

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1. Turn the ignition switch OFF.
2. Disconnect the evaporator temperature sensor connector.
3. Measure resistance between terminal "+" and "-" of evaporator temperature sensor.
4. Connect the evaporator temperature sensor connector.
5. Run the engine and turn the A/C switch ON, then measure the voltage between the terminals of harness connector. EVAPORATOR TEMPERATURE SENSOR SPECIFICATION Evaporator core temperature [°C(°F)] Resistance [kohms] Voltage [V] -20(-4) 29.42 3.732 -10(14) 18.01 3.215 0(32) 11.36 2.659 10(50) 7.362 2.12 20(68) 4.892 1.642 30(86) 3.326 1.248 40(104) 2.309 0.938 50(122) 1.635 0.700

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1. Disconnect the negative (-) battery terminal.
2. Disconnect the evaporator temperature sensor connector (A).
3. Remove the evaporator temperature sensor (A) by pulling it out after rotating 90° in a counterclockwise direction.
4. Install in the reverse order of removal.

The In-car air temperature sensor is built in the heater & A/C control unit.

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.

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The photo sensor is located at the center of defrost nozzles.

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.

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1. Turn the ignition switch ON.
2. Connect the GDS.
3. Emit intensive light toward photo sensor using a lamp, and check the output voltage change.
4. The voltage will rise with higher intensive light and reduce with lower intensive light.

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1. Disconnect the negative (-) battery terminal.
2. With a flat-head screwdriver, remove the photo sensor (A) from the center of defrost nozzle after disconnecting the connector (B).
3. Install in the reverse order of removal.

The ambient temperature sensor is located at the front of the condenser and detects ambient air temperature. It is a negative type thermistor; resistance will increase with lower temperature, and decrease with higher temperature.

The sensor output will be used for discharge temperature control, temperature regulation door control, blower motor level control, mix mode control and in-car humidity control.

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Note. If the ambient temperature is below 1.0°C (33.8°F), the A/C compressor will stop. The compressor will operate manually.

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1. Turn the ignition switch OFF.
2. Disconnect ambient temperature sensor.
3. Check the resistance of ambient temperature sensor between terminal "+" and "-" whether it is changed by changing of the ambient temperature. AMBIENT TEMPERATURE SENSOR SPECIFICATION Ambient temperature [°C(°F)] Resistance [kohms] Voltage [V] -30(-22) 507 4.720 -20(-4) 284.5 4.522 -10(14) 164.2 4.225 0(32) 97.5 3.821 10(50) 59.6 3.322 20 (68) 37.46 2.772 30(86) 24.18 2.227 40(104) 16 1.735 50(122) 10.83 1.323
4. If the measured resistance is not within specification, substitute with a known-good ambient temperature sensor and check for proper operation.
5. Replace the ambient temperature sensor if it is proved that there is a problem with the sensor.

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1. Disconnect the negative (-) battery terminal.
2. Remove the engine room RH side under cover. (Refer to " «ENGINE AND TRANSAXLE ASSEMBLY»(ref-536073-S40970354632013031400000) ")
3. Disconnect the ambient temperature sensor connector (A).
4. Remove the ambient temperature sensor (A).
5. Install in the reverse order of removal.

The Auto Defogging Sensor is installed on the front windshield glass. The Auto Defogging Sensor senses moisture on the windshield. The air conditioner control module receives the signal from the sensor and eliminates fog by controlling the intake actuator, A/C, auto defogging actuator, blower motor rpm, and mode actuator.

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The cluster ionizer helps to clean up odors in the vehicle or from the air-conditioner system.

When the ignition switch ON, the ionizer runs a "CLEAN" mode and then a "ION" mode, switching every about 15 minutes. In the "CLEAN" mode, the cluster ionizer generates negative and positive ions to help clean smells from the air In the "ION" mode, the cluster generates negative ions and cleans inside air of a vehicle.