Fan Motor Connector Output Check; Power Supply Waveforms Check; Electronic Expansion Valve Check - Daikin FTXG20LV1BW Service Manual

SiBE041401E
5.2

Fan Motor Connector Output Check

Check No.02 1. Check the connection of connector.
2. Check the motor power supply voltage output (pins 4 - 7).
3. Check the motor control voltage (pins 4 - 3).
4. Check the rotation command voltage (pins 4 - 2).
5. Check the rotation pulse (pins 4 - 1).
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 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
4. Check the continuity between the pins 1 - 6, 2 - 6, 3 - 6, 4 - 6. If there is no continuity between the
5. If the continuity is confirmed in step 3, the outdoor unit PCB is faulty.
Service Diagnosis
S200
7
6
5
4
3
2
1
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).
and check the continuity using a multimeter.
pins, the EV coil is faulty.
S20
Motor power supply voltage (310 ~ 340 VDC)
Unused
Unused
GND
Motor control voltage (15 VDC)
Rotation command voltage (1~ 6.5 VDC)
Rotation pulse input
Fig.2
(R1736)
Harness 5P
(5)
Check
6P Connector
1 2 3 4 5 6
(R16386)
(R19942)
1 - 6
2 - 6
3 - 6
4 - 6
Check
(R1444)
94