Hyundai Accent: Air Conditioning System / A/C Pressure Transducer

- Description The A/C Pressure Transducer (APT) converts the pressure value of high pressure line into voltage value after measuring it. By converted voltage value, engine ECU controls the cooling fan by operating it high speed or low speed. Engine ECU stops the operation of the compressor when the temperature of refrigerant line is very high or very low irregularly to optimize air conditioning system. - Inspection

• Before measuring the pressure of the refriferant line, check whether the refrigerant amount is charged in accordance with the specified charging amount.(Refer to Heating, Ventilation, Air Conditioning - "Specifications")

1.Turn the ignition switch OFF.

2.Install the refrigerant recovery/recycling/charging system.(Refer to Air Conditioning System - "Repair procedures")

3.Turn ON the ignition switch, put into operation the air conditioner.

4.Calculate the reference voltage of the Recovery/Recycle/Recharge machine high pressure value using the formula below.

Reference voltage (V) = 0.0088 * pressure(psi) + 0.37

5.Measure the sensor output voltage between terminal "1" and "2".

6.If the reference voltage value and the sensor output voltage value are close to each other, the air conditioner pressure transducer is normal.

7.If 0V is output or the reference voltage value and sensor output voltage value are not close to each other, replace the air conditioner pressure transducer.

• Check if the output voltage changes when the high pressure value of the refrigerant line changes.

1.The heating, ventilation and air conditioning can be quickly diagnosed failed parts with vehicle diagnostic system (GDS).※ The diagnostic system (GDS) provides the following information.(1) Self diagnosis : Checking the failure code (DTC) and display.(2) Current data : Checking the system input / output data state.(3) Actuation test : Checking the system operation condition.(4) Additional function : Other controlling such as he system option and zero point adjustment.

2.Select the 'Car model' and the system to be checked in order to check the vehicle with the tester.

3.Select the 'Current data' menu to search the current state of the input / output data.The input / output data for the sensors corresponding to the A/C Pressure Transducer can be checked.

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 :10.0 - 12.0 N.m (1.02 - 1.22 kgf.m, 7.38 - 8.82 lb-ft)

5.To install, reverse the removal procedure.