46
C Check of indoor electronic control P.C. board and indoor fan motor
MSZ-GS06/09/12/15NA
MSY-GS09/12/15NA
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?
Yes
No
Measure the resistance between
CN211 and of the indoor fan motor
connector.
Short circuit:
Replace the indoor fan motor.
Turn OFF the power supply.
Check both “parts side” and “pattern
side” of the indoor terminal P.C.
board visually.
Replace the varistor (NR11)
and fuse (F11). *3
Are the varistor (NR11)
burnt and the fuse (F11)
blown?
No
No
Yes
Yes
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 (-) of indoor fan
motor connector. *1, *2
Yes
Is the resistance 1MΩ or more?
Replace the fuse (F11) and the
indoor fan motor. *3
No
Replace the fuse (F11). *3
Measure the resistance of resistor
(R111) on the indoor power P.C. board.
No
Is the resistance of resistor
(R111) approximately 4 Ω?
No
Replace the indoor power P.C.
board, the indoor terminal P.C.
board and the indoor fan motor.
Replace the indoor electronic control P.C. board.
Measure the resistance of the vane
motor coil.
(Refer to 9-5.)
Short circuit:
Replace the vane motor and the indoor
electronic control P.C. board.
*1. The fan motor connector's lead wire is red, whereas
is black.
*2. Connect “+” of the multimeter to fan motor connector's
lead wire, and “-” to lead wire, otherwise the
resistance cannot be measured properly.
*3. Please replace the fuse after removing the indoor
terminal P.C. board from the electrical box.
Is there approximately 5 V DC
between 5 V (+) and GND (-) of the
indoor electronic control P.C. board?
Is there approximately 9 to 13 V DC
between 12 V (+) and GND (-) of the
indoor electronic control P.C. board?
Are connector CN10A on the
indoor electronic control P.C. board
or lead wires disconnected?
Yes
Replace the indoor fan motor.
Yes
Connect the connector or repair
disconnection.
Yes
No
GND
CN10A
12 V DC
5 V DC
Indoor electronic control
P.C. board
Indoor power P.C. board
R111
CN211
Indoor terminal
P.C. board
Fuse
(F11)
Varistor
(NR11)
CN151
OBH874A