Additional Indoor Blower Motor (B3) Troubleshooting; Module Test (Emerson); Indoor Blower Motor (B3) Control Connections (Emerson) - Lennox CBX40UHV Series Installation And Service Procedure

CONTROL MODULE
3-PIN JACK
NTC
THERMISTOR
Figure 18. Module Test (Emerson)

Additional Indoor Blower Motor (B3) Troubleshooting

1. If motor shaft spins freely in both directions, proceed to
next step. If not, replace motor.
2. Check the motor to control harness for any damage.
A. If harness or terminals are damaged replace the
motor.
P48 5 Pin
P49 4 Pin
Figure 20. Indoor Blower Motor (B3) Control Connections (Emerson)
CBX40UHV
B. If there is no damage, proceed to next step.
3. Check resistance between each of the three-phase
terminals in the motor harness as illustrated in figure
19. Resistance between any two contacts should be
equal. If resistance between any two contacts are not
equal, or if any resistance shows open or
short-circuited, replace the motor.
Figure 19. Motor Test (Emerson)
P48 (5-PIN)
MOTOR
J48 5 Pin Line Voltage Connector
J49 4 Pin Control Connector
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MOTOR 3-PIN
PLUG
P49 (4-PIN)
CONTROL MODULE