Daikin Wall Mounted Type Indoor Unit FTXS25G2V1B

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

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

If OK in both steps 1 and 2, select the part to replace

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

Thermistors disconnected from the PCB?

Enter the resistance of each thermistor

Select the model of the thermistor

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

Connector for the PCB disconnected?

Enter the resistance of the thermistor

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)

Sign off on the fan motor connector check

Warning: This procedure requires trained personnel with PPE!

EV connector correctly inserted in the PCB

All EVs generate latching sound after power cycle

If any EV does not generate latching sound, proceed to next step

Continuity between pins 1 - 6 and 3 - 6

Continuity between pins 2 - 5 and 4 - 5

If no EV generates latching sound, the outdoor unit PCB is faulty

Good coil mounted in EV unit generates latching sound

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