Hall Ic Check; Power Supply Waveforms Check - Daikin FLKS25BAVMB Service Manual

SiBE05-722EE
5.2

Hall IC Check

Check No.04 1. Check the connector connection.
2. With the power on, operation off, and the connector connected, check the following.
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
Service Diagnosis
(1) Output voltage of about 5 V between pins 1 and 3.
(2) Generation of 3 pulses between pins 2 and 3 when the fan motor is operating.
If NG in step (1) Defective PCB
If NG in step (2) Defective Hall IC
If OK in both steps (1) and (2)
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)
Replace the PCB (control PCB).
Replace the fan motor.
Replace the PCB (control PCB).
S7
Gray (power supply)
1
2 Purple (signals)
3 Blue (grounding)
Fig.2
(R1736)
(R14211)
Check
(R1444)
103