Air Conditioning System: Overview Kia Carnival III

Scheme 1

1. R-134a liquid refrigerant is highly volatile. A drop on the skin of your hand could result in localized frostbite. When handling the refrigerant, be sure to wear gloves.
2. It is standard practice to wear goggles or glasses to protect your eyes, and gloves to protect your hands. If the refrigerant splashes into your eyes, wash them with clean water immediately.
3. The R-134a container is highly pressurized. Never leave it in a hot place, and check that the storage temperature is below 52°C (126°F)
4. An electronic leak detector should be used to check the system for refrigerant leakage. Bear in mind that the R-134a, upon coming into contact with flame, produces phosgene, a highly toxic gas.
5. Use only recommended the lubricant for R-134a systems. If lubricants other than the recommended one used, system failure may occur.
6. PAG lubricant absorbs moisture from the atmosphere at a rapid rate, therefore the following precautions must be observed: When removing refrigerant components from a vehicle, cap immediately the components to prevent from the entry of moisture. When installing refrigerant components to a vehicle, do not remove the cap until just before connecting the components. Complete the connection of all refrigerant tubes and hoses without delay to prevent the A/C system from taking on moisture. Use the recommended lubricant from a sealed container only.
7. If an accidental discharge in the system occurs, ventilate the work area before resuming service.

Scheme 2

1. Never open or loosen a connection before discharging the system.
2. Seal the open fittings of components with a cap or plug immediately to prevent intrusion of moisture or dust.
3. Do not remove the sealing caps from a replacement component until it is ready to be installed.
4. Before connecting an open fitting, always install a new sealing ring. Coat the fitting and seal with refrigerant oil before making the connection.

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.

Scheme 3

Description

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

Scheme 4

Scheme 5

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 = 0.00878835 * Pa + 0.37081095
3. If the measured voltage value is not specification, replace the A/C pressure transducer.

Scheme 6

1. Disconnect the negative (-) battery terminal.
2. Recover the refrigerant with a recovery/charging station.
3. Disconnect A/C pressure transducer connector (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.

Scheme 7

Scheme 8

1. Ignition "OFF"
2. Disconnect evaporator temperature sensor.
3. Using the multi-tester, Measure resistance between terminal "1" and "2" of evaporator temperature sensor. Specification RESISTANCE SPECIFICATION Evaporator core temperature (°C (°F)) Resistance (kohms) -10 (14) 43.35 0 (32) 27.62 10 (50) 18.07 15 (59) 14.75 30 (86) 8.30 40 (104) 5.81 50 (122) 4.15
4. If the measured resistance is not specification, substitute with a known-good evaporator temperature sensor and check for proper operation.
5. If the problem is corrected, replace the evaporator temperature sensor.

Scheme 9

Scheme 10

1. Disconnect the negative (-) battery terminal.
2. Remove the center lower side cover (B).
3. Disconnect the evaporator sensor connector (A).
4. Loosen 2 screws and then remove the evaporator sensor cover (B).
5. Remove the evaporator sensor. CAUTION: Take care that evaporator core pins are not bent.
6. Installation is the reverse order of removal.

Scheme 11

1. In-car air temperature sensor is located at the center fascia lower 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 12

1. The photo sensor (A) is located at the center 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.

Scheme 13

Scheme 14

1. Ignition "ON"
2. Using the scan tool.
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.

Scheme 15

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

1. 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 temperatures.
2. 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. NOTE: If the ambient temperature is below 0°C (32°F), the A/C compressor will be stopped. The compressor will be manually operated.

Scheme 16

Scheme 17

1. Ignition "OFF"
2. Disconnect ambient temperature sensor.
3. Check the resistance of ambient temperature sensor between terminals 1 and 2 whether it is changed by changing of the ambient temperature. Specification RESISTANCE SPECIFICATION Ambient temperature (°C (°F)) Resistance between terminals 1 and 2 (kohms) -10 (14) 158.18 ± 4.9% 0 (32) 95.10 ± 3.9% 10 (50) 58.80 ± 2.9% 20 (68) 37.32 ± 1.9%
4. If the measured resistance is not specification, substitute with a known-good ambient temperature sensor and check for proper operation.
5. If the problem is corrected, replace the ambient temperature sensor.

Scheme 18

1. Disconnect the negative (-) battery terminal.
2. Remove the front bumper. Refer to «FRONT BUMPER»(ref-674590-S29072787842014120300000) .
3. Remove the ambient temperature sensor (A).
4. Installation is the reverse order of removal.

Scheme 19

1. Humidity sensor is located at the lower crash pad and detected in-car humidity for in-car humidity control.
2. If ambient air temperature or in-car humidity is outside certain range, it will turn on A/C to control in-car humidity preventing in car fogging. Air conditioner operation depends on ambient temperature and humidity.

Scheme 20