Hyundai Elantra (CN7): Air Conditioning System / Evaporator Temperature Sensor

Hyundai Elantra (CN7) 2021-2025 Service Manual / Heating, Ventilation and Air Conditioning / Air Conditioning System / Evaporator Temperature Sensor

Description and operation

Description

The evaporator temperature sensor will detect the evaporator core temperature and interrupt compressor relay power in order to prevent evaporator from freezing by excessive cooling. The evaporator temperature sensor has the Negative Temperature Coefficient (NTC). Electrical resistivity of NTC will increase with decreasing temperature and decrease with increasing temperature.

Repair procedures

Inspection

1.	Turn the ignition switch ON.

2.	Turn the A/C switch ON.

Measure the resistance between terminal "+" and "-" of the evaporator temperature sensor.

Evaporator core temperature	Resistance [KΩ]	Voltage [V]
[°C (°F)]	Resistance [KΩ]	Voltage [V]
-10 (14)	43.35	2.96
0 (32)	27.62	2.4
10 (50)	18.07	1.88
20 (68)	12.11	1.44
30 (86)	8.3	1.08
40 (104)	5.81	0.81

Replacement

1.	Disconnect the negative (-) battery terminal.

2.	Remove the evaporator core. (Refer to Heater - "Evaporator Core")

3.	Remove the evaporator temperature sensor (A) front evaporator core.

4.	To install, reverse the removal procedure.

❮A/C Pressure Transducer

Description and operation DescriptionThe A/C Pressure Transducer (APT) converts the pressure value of high pressure line into voltage value after measuring it.

In-car Sensor❯

Description and operation DescriptionThe 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.

Other information:

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