Daikin Wall Mounted Type Indoor Unit FTXG25JV1BS

Warning: This procedure requires trained personnel with PPE!

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

If no continuity between the pins, the EV coil is faulty

All EVs generate latching sound after mounting a good coil

If latching sound is not generated, the EV unit is faulty

If latching sound is generated, the outdoor unit PCB is faulty

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: 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?

Sign off on the thermistor resistance check

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: This check requires trained personnel with PPE!

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

Is the power supply waveform a sine wave as shown in Fig.1?

Is there waveform disturbance near the zero cross as shown in the sections circled in Fig.2?

Upload a photo of the measured waveform

Sign off on the power supply waveform check