Mitsubishi Electric MUZ-GA35VA-E3 Service Manual page 43

Outdoor fan motor does not operate.
Check of outdoor fan motor
I
MUZ-GA35VA
MUZ-GA35VAH
Is the resistance
between each terminal of
outdoor fan motor normal?
(Refer to 11-5.)
No
Replace the outdoor fan
motor.
Inverter does not operate.
Check of power supply
J
Disconnect the connector
(CN61) between compressor and
intelligent power module.
Turn ON power supply and press
EMERGENCY OPERATION
switch.
Does the left lamp of
OPERATION INDICATOR
lamp on the indoor unit
light up?
Yes
Is there voltage
280V ~ 370V DC
between DB61 (+) and
DB61 (–) on the
inverter P.C. board?
(Refer to 11-7.1.)
No
Check the electric
parts in main circuit.
Disconnect CN932
Yes
from the inverter
P.C. board.
Inverter P.C. board
(Solder side)
CN931
CN932
Rectify indoor/ outdoor
connecting wire.
Is there voltage 230V AC
No
between the indoor
terminal block S1 and
S2?
Dose LED on the inverter
Yes
P.C. board light up or
flash? (Refer to 11-7.1.)
If light up,ok.
If flash, refer to
11-4.
Turn ON the
power supply.
( Fixed to either 5V or 0V DC)
Yes
Replace the indoor
No
electronic control
P.C. board.
No
Replace the inverter
P.C. board.
Yes
DB61
Inverter P.C. board
(Solder side)
43
Rotate the outdoor fan slowly
by hand, and measure the
voltage of CN931 (Measurement
of feedback output).
Between 1(+) and 5(-)
Between 2(+) and 5(-)
Between 3(+) and 5(-)
Does the voltage between
each terminal repeat 5V
No
and 0V DC by turns?
Yes
Does the outdoor fan
rotate smoothly?
No
Yes
Check the inverter P.C. board.
(Refer to 11-6. N)
280V~370V DC