Daikin Super Multi Plus D-Series, Service Manual

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SiEBE18-526 Troubleshooting for RA Indoor Unit
Troubleshooting 267
4.6.4 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.
„
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)
4.6.5 Hall IC Check
Check No.16 1. Check the connector connection.
2. With the power ON, operation OFF, and the connector connected, check the following.
∗
Output voltage of about 5 V between pins 1 and 3.
∗
Generation of 3 pulses between pins 2 and 3 when the fan motor is operating.
Failure of (1) Æ faulty PCB Æ Replace the PCB.
Failure of (2) Æ faulty hall IC Æ Replace the fan motor.
Both (1) and (2) result
Æ
Replace the PCB.
The connector has 3 pins, and there are two patterns of lead wire colors.
[Fig.1] [Fig.2]
Gray (power supply)
1
2
3
1
2
3
Purple (signals)
Blue (grounding)
White (power supply)
White with black line (signals)
White with manufacturer mark (grounding)
(R1990)