Mitsubishi Electric MXZ-2D33VA Service Manual page 147

MXZ-6D122VA
Disconnect CNF1 and measure the
resistance of the outdoor fan motor.
Is the resistance of outdoor fan motor
normal? (Refer to right table)
Yes
Does the outdoor fan motor rotate smoothly?
Yes
Turn on the power supply to start operation
and measure the voltage of connector CNF1.
Is the voltage of connector CNF1
normal? (Refer to right table.)
Yes
Turn OFF the power supply and connect
the connector CNF1.
Turn ON the power supply and measure
the voltage of connector CNF1 while
rotating the motor by the hand.
Does the voltage between pin7 and pin4
of connector CNF1 repeat 0V and 5V?
Yes
Start operation.
Does the fan motor operate for about
5 seconds?
Yes
Replace the outdoor control P.C. board.
OBH626K
No
Replace the outdoor fan motor.
No
Replace the outdoor fan motor.
CNF1 Voltage
pin1 - pin4 325 VDC
pin5 - pin4 15 VDC
pin6 - pin4 1 - 5 VDC
* To measure the voltage, connect the negative (-)
end of the tester to pin4.
* Voltage between pin4 and 6 should be measured
within 1 minute after the operation starts.
No
Replace the outdoor control P.C. board.
No
Replace the outdoor fan motor.
No
Replace the outdoor fan motor.
147
CNF1 Outdoor control
P.C. board
Measuring points Resistance
pin1 - pin4
pin5 - pin4
pin6 - pin4
pin7 - pin4
* To measure the resistance, connect
the negative (-) end of the tester to pin4.