Carrier 40MB C Series Service Manual page 21

Index 1:
1 Indoor DC fan motor (control chip is inside fan motor)
Power on and when the unit is in standby, measure the voltage of pin1−pin3, pin4−pin3 in fan motor connector. If the value of the
voltage is not in the range showing in below table, the PCB must have problems and need to be replaced.
DC motor voltage input and output
No. Color
1 Red
2 ---
3 Black
4 White
5 Yellow
6 Blue
Fig. 27 – Indoor DC fan motor
Table 8—Signals
Signal
Vs/Vm
---
GND
Vcc
Vsp
FG
21
Voltage
200~380V
---
0V
13.5~16.5V
0~6.5V
13.5~16.5V