Daikin Ducted‑Style Indoor Unit ATXS50G2V1B

Check the connection of connector

Check motor power supply voltage output (pins 4 - 7)

Check motor control voltage (pins 4 - 3)

Check rotation command voltage output (pins 4 - 2)

Check rotation pulse input (pins 4 - 1)

Warning: Disconnect the connectors of the thermistors from the PCB before proceeding

Thermistors disconnected from the PCB?

Enter the resistance of Thermistor 1

Enter the resistance of Thermistor 2

Enter the resistance of Thermistor 3

Refer to the table and graph for normal temperature and resistance relationship

Are the resistance readings within the normal range?

For models with thermistor directly mounted on the PCB, disconnect the connector for the PCB and measure

Thermistor directly mounted on the PCB disconnected?

EV connector correctly inserted in the PCB

All EVs generate latching sound after power cycle

Continuity between pins 1 - 6 and 3 - 6

Continuity between pins 2 - 5 and 4 - 5

Good coil generates latching sound when mounted in the EV unit

Note: Latching sound varies depending on the valve type

Warning: Operating with a defective electronic expansion valve may cause problems

Sign off on the electronic expansion valve check

With the power on, operation off, and the connector connected, check the following

Output voltage of about 5 V between pins 1 and 3

Generation of 3 pulses between pins 2 and 3 when the fan motor is operating

If NG in step 1 or 2, select the defective part

Warning: This check requires trained personnel with PPE!

Measure the power supply waveform between No. 1 and No. 2 on the terminal board

Upload a photo of the measured waveform

Is the power supply waveform a sine wave (Refer to Fig.1)?

Is there waveform disturbance near the zero cross (Refer to sections circled in Fig.2)?

Sign off on the power supply waveform check