Daikin FTXS09DVJU Service Manual page 187

Check
5.1.8 Power Supply Waveforms Check
Check No.10 Measure the power supply waveform between pins 1 and 3 on the terminal board, and check the
waveform disturbance.
[Fig.1]
5.1.9 Inverter Units Refrigerant System Check
Check No.11
176
Check to see if the power supply waveform is a sine wave (Fig.1).
Check to see if there is waveform disturbance near the zero cross (sections circled in Fig.2)
Refrigerant system check
Is
the discharge
thermister disconnected from
the holder?
NO
Is any moisture
found in sight glass.
NO
Check for gas leaks.
See the section on insufficient gas
detection.
YES
[Fig.2]
YES
YES
Conduct the check after operating the
equipment for a sufficient length of time.
SiUS04-702
Correct the problem.
Conduct vacuum drying.
Replace the refrigerant.
(R1445)
Service Diagnosis