Daikin Indoor Unit Wall Mounted Type Air Conditioner ATX20K2V1B

EV connector correctly connected to the PCB

EV generates a latching sound when power is turned off and on again

Continuity confirmed when connector is disconnected and checked with 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

Fan motor wire breakdown / short circuit check

1. Check the connector for connection.

3. Check if each resistance at the phases U - V and V - W is 90 Ω ~ 100 Ω (between the pins; 12 - 9, and between 9 - 6).

1. Check the connector for connection.

2. Check the motor control voltage is generated (between the pins 2 - 3).

1. Check the connector for connection.

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 without touching each other?

Activate power transistor test operation from the indoor unit

Pressed the center of the TEMP button and the OFF button on the remote controller at the same time?

Warning: Ensure the voltage between (+) and (–) of the diode bridge (DB1) is about 0 V before checking.

Enter the voltage between (+) and (–) of the diode bridge (DB1)

Measure the resistance between the pins of the DB1 referring to the table below.

Enter the resistance between the pins of the DB1

Is the resistance ∞ or less than 1 kΩ?

If the resistance is ∞ or less than 1 kΩ, short circuit occurs on the main circuit.

Sign off on the main circuit short check

Warning: Ensure the voltage between (+) and (–) of the power module is about 0 V before proceeding

Disconnect the compressor harness connector from the outdoor unit PCB. To disengage the connector, press the protrusion on the connector.

Connector disengaged successfully?

Measure resistance between the terminals of the power module and the terminals of the compressor with a multimeter.

Enter the resistance measurement

Evaluate the measurement results

Sign off on the power module check