Daikin Indoor Unit Multi-Split Type Air Conditioner CTXG12QVJUW

Warning: This procedure requires trained personnel with PPE!

If power is not turned off, stop the procedure and turn off the power

Is the charged voltage of the built-in smoothing electrolytic capacitor 10 VDC or below?

If the charged voltage is above 10 VDC, wait until it drops to 10 VDC or below

Are the terminals from the compressor removed?

Are the terminals connected to the terminals of the inverter analyzer?

Warning: Do not let the terminals (U,V,W) touch each other. High voltage is applied.

Is the power transistor test operation activated from the outdoor unit?

Control voltage between the pins 4 - 3

Rotation command voltage between the pins 4 - 2

Pulses at the pins 4 - 1 when the outdoor fan motor is rotated 1 turn by hand

Outdoor fan motor functioning properly?

Warning: This procedure requires trained personnel with PPE!

Main circuit checked for short circuit?

Ensure firm contact between the multimeter probes and the test points.

Sign off on the capacitor voltage check

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 any 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

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

Voltage between (+) and (–) of the power module is about 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 disconnected from the outdoor unit PCB

Measure resistance between the (+) or (–) terminal of the power module and the U, V, or W terminal of the compressor with a multimeter.

Enter the resistance measurement

Evaluate the measurement results

Sign off on the power module check