Daikin Indoor Unit Wall Mounted Type Air Conditioner FTX35K2V1B

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

Control voltage between the pins 3 - 4

Rotation command voltage between the pins 2 - 4

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

Rotation pulses at the pins 1 - 4 when the fan motor is rotated 1 turn by hand

Outdoor fan motor functioning properly?

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

Thermistors disconnected from the PCB?

Measure the resistance of each thermistor using a multimeter

If the room temperature thermistor is soldered on a PCB, remove the PCB from the control PCB to measure the resistance

Room temperature thermistor removed from PCB?

Measure the resistance of the room temperature thermistor

If the connector of indoor heat exchanger thermistor is soldered on a PCB, remove the thermistor and measure the resistance

Indoor heat exchanger thermistor removed from PCB?

Measure the resistance of the indoor heat exchanger thermistor

Warning: This check requires trained personnel with PPE!

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

Is the power supply waveform a sine wave (Fig.1)?

Is there waveform disturbance near the zero-cross (sections circled in Fig.2)?

Upload a photo of the measured waveform

Sign off on the power supply waveforms 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 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 power module is about 0 V before proceeding

Compressor harness connector disconnected from the outdoor unit PCB

Procedure to measure resistance between the terminals of the power module and the terminals of the compressor

Enter the resistance measurement

Evaluate the measurement results

Sign off on the power module check