Carrier 40MAQ Series Service Manual page 36

2 Outdoor DC Fan Motor (control chip is in the outdoor PCB)
No. 1
Color Orange
Signal Hu
Color
Signal
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 has
an issue and needs to be replaced. Otherwise, proceed to step 2.
2 Power on and when the unit is in standby, measure the voltage of pin 4- 5 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 voltage of pin 1- 5, pin 2- 5, and pin 3- 5 in the feedback signal connector. If any voltage is not
positive voltage fluctuation, the fan motor has an issue and must be replaced.
Fig. 39 – Outdoor DC Fan Motor
2
Grey White
Hv Hw
Red
W
36
3 4
Pink
Vcc
Blue
V
5
Black
GND
Yellow
U