Daikin Slim Duct Concealed Indoor Unit CDXS18LVJU

Output voltage between pins 1 and 3

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

Warning: Ensure that the voltage between (+) and (–) of the power module (PM1) is approx. 0 V before proceeding.

Voltage between (+) and (–) of the power module (PM1) is approx. 0 V?

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

Compressor harness connector successfully disconnected?

Measure resistance between the terminals of the power module and the terminals of the compressor with a multi-tester.

Enter the resistance measurement

Evaluate the measurement results

Sign off on the power module 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: Disconnect the connectors of the thermistors from the PCB before proceeding

Thermistors disconnected from the PCB?

Measure the resistance of the room temperature thermistor

Remove the display PCB from the control PCB to measure the resistance

Display PCB removed from the control PCB?

Measure the resistance of the indoor heat exchanger thermistor

Remove the thermistor from the PCB to measure the resistance

Thermistor removed from the PCB?

Measure the resistance of the removed thermistor

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?

Is there waveform disturbance near the zero cross?

Sign off on the power supply waveform check