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38MARB: Service Manual
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
33
DIAGNOSIS AND SOLUTION (CONT)
Outdoor DC Fan Motor (DC motor that controls the chip on the PCB)
1. Release the UVW connector. Measure the resistance of U-V, U-W, V-W. If the resistance is not equal to each other, the fan motor is faulty and must be
replaced. Otherwise, proceed to step 2.
2. Power on the unit and when the unit is in standby, measure the pin4-5 voltage in the feedback signal connector. If the value is not 5V, change the PCB.
Otherwise, proceed to step 3.
3. Rotate the fan by hand, measure the pin1-5, pin 2-5 and pin 3-5 voltage levels in the feedback signal connector. If any voltage is not in the positive
voltage fluctuation, the fan motor is faulty and must be replaced.
Fig. 32 — Outdoor DC Fan Motor (DC motor that controls the chip on the PCB)
NO.
1
2
3
4
5
Color
Orange
Grey
White
Pink
Black
Signal
Hu
Hv
Hw
Vcc
GND
Color
Red
Blue
Yellow
Signal
W
V
U