Mitsubishi Electric MSZ-EF18VGW-E1 Service Manual page 41

MSZ-EF50VG- ,
,
E2 ET2
MSZ-EF50VGK- ,
E1 ET1
Turn OFF the power supply.
Remove indoor fan motor connector CN211
from indoor power P.C. board and vane
motor connector CN151 from the indoor
electronic control P.C. board and turn ON
the power supply.
Does the unit operate with the remote
controller?
Does OPERATION INDICATOR lamp light
up by pressing the emergency operation
switch?
No
Turn OFF the power supply.
Check both "parts side" and "pattern
side" of the indoor power P.C. board
visually.
Measure the resistance of reactor
(L112) on the indoor power P.C.
board.
Indoor power
P.C. board
CN211
Indoor electronic
control P.C. board
OBH831D
ET3
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ER1 E2 ET2 ER2
Measure the resistance of indoor fan
motor.
Refer to 10-5.
Measure the resistance of the vane
motor coil.
Yes
Refer to 10-5.
Replace the varistor (NR11)
and fuse (F11). 3
Is the varistor (NR11)
burnt and the fuse (F11)
blown?
Be sure to check both the fuse
and the varistor in any case.
Is the fuse (F11) blown
only?
Measure the resistance between
CN211 (+) and
motor connector. 1, 2
Is the resistance 1MΩ or more?
Replace the fuse (F11). 3
Fuse (F11)
Varistor
(NR11)
L112
CN102
Replace the indoor electronic control P.C. board.
Yes
No
No
Yes
1. The fan motor connector's
whereas
2. Connect "+" of the multimeter to fan motor connector's
lead wire, and "-" to
(-) of indoor fan
resistance cannot be measured properly.
3. Please replace the fuse after removing the indoor
power P.C. board from the electrical box.
Replace the fuse (F11) and the
indoor fan motor. 3
No
Yes
Is the resistance of
reactor (L112) approximately 2.2 Ω?
Yes
Is there approximately 5 V DC between
5 V (+) and CN102 (-) of the indoor
electronic control P.C. board?
Is there approximately 9 V to 13 V DC
between 12 V (+) and CN102 (-)
of the indoor electronic control P.C.
board?
No
Are connector CN102 on the
indoor electronic control P.C.
board or lead wires discon-
nected?
No
41
Short circuit:
Replace the indoor fan motor.
Short circuit:
Replace the vane motor and the indoor
electronic control P.C. board.
lead wire is red,
is black.
lead wire, otherwise the
Replace the indoor
power P.C. board and
No
the indoor fan motor.
Replace the indoor fan motor.
Yes
Connect the connector or repair discon-
nection.
Yes