Daikin Indoor Unit Floor Standing Type Air Conditioner FDMQ24WVJU9

EV connector correctly connected to the PCB

Turn the power off and on again, did the EV generate a latching sound?

Disconnect the connector and check the continuity using a multimeter

Check the continuity between the pins

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

If the continuity is confirmed, the outdoor unit PCB (main PCB) is faulty

Sign off on the electronic expansion valve check

With the fan motor connector disconnected, measure the resistance between each pin

Is the resistance value more than the value mentioned in the table?

Note: A measurement error might occur in the resistance value depending on the measurement conditions and the method.

Sign off on the Indoor Fan Motor Connector Check

Warning: This procedure requires trained personnel with PPE!

Install an inverter analyzer instead of a compressor.

Charged voltage of the built-in smoothing electrolytic capacitor dropped to 10 VDC or below?

Terminals removed from the compressor?

Terminals connected to the terminals of the inverter analyzer?

Activate the power transistor test operation from the outdoor unit.

Power transistor test operation activated?

Diagnose method (Diagnose according to 6 LEDs lighting status.)

Voltage between (+) and (–) of the diode bridge (DB1)

If voltage is not about 0V, stop the procedure and report the issue

Resistance between the pins of the DB1

If the resistance is  or less than 1 k, short circuit occurs on the main circuit.

Does the main circuit have a short circuit?

Sign off on the main circuit short check

Ensure that the voltage is within 320 VDC

Set operation off and power off. Disconnect the connector S70 or S71

Check that the voltage between the pins 4 - 7 is 320 VDC

Check that the control voltage between the pins 4 - 3 is 15 VDC

Check that the rotation command voltage between the pins 4 - 2 is 0 ~ 6.5 VDC

Keep operation off and power off. Connect the connector S70 or S71

Check whether 4 rotation pulses (0 ~ 15 VDC) are input at the pins 4 - 1 when the fan motor is rotated 1 turn by hand

When the fuse is melted, check the outdoor fan motor for proper function

If NG in step 2 -> Defective PCB -> Replace the outdoor unit PCB (main PCB)