Power Supply Waveforms Check; Electronic Expansion Valve Check - Daikin FTKN09NMVJU Service Manual

Check
5.3

Power Supply Waveforms Check

Check No.11 Measure the power supply waveform between No. 1 and No. 2 on the terminal board, and check
the waveform disturbance.
Fig.1
5.4

Electronic Expansion Valve Check

Check No.12 Conduct the followings to check the electronic expansion valve (EV).
1. Check if the EV connector is correctly connected to the PCB.
2. Turn the power off and on again, and check to see if the EV generates a latching sound.
3. If the EV does not generate a latching sound in the above step 2, disconnect the connector and
4. Check the continuity between the pins 1 - 6, 2 - 6, 3 - 6, and 4 - 6 (between the pins 1 - 5, 2 - 5,
5. If the continuity is confirmed in step 3, the outdoor unit PCB (main PCB) is faulty.
93
Check if the power supply waveform is a sine wave (Fig.1).
Check if there is waveform disturbance near the zero-cross (sections circled in Fig.2).
check the continuity using a multimeter.
3 - 5, 4 - 5 for the 5P connector models). If there is no continuity between the pins, the EV coil is
faulty.
Harness 5P
(5)
S20 Check
6P Connector
1 2 3 4 5 6
Fig.2
Harness 5P
1 - 6
S20
5P Connector
2 - 6
3 - 6
1 2 3 4 5
4 - 6
(R16386)
SiUS041501E
1 - 5
2 - 5
Check
3 - 5
4 - 5
(R20506)
Service Diagnosis