Mitsubishi Electric MSZ-D30NA Service Manual page 109

MSZ-GE24NA
MSY-GE24NA
Turn OFF the power supply.
Remove indoor fan motor connector CN211 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 EMERGENCY OPERATION switch?
No
Turn OFF the power supply.
Check both "parts side" and "pattern
side" of the indoor electronic control P.C.
board visually.
Indoor terminal Indoor electronic
P.C. board control P.C.Board
Fuse
(F11)
Varistor
(NR11)
OBH548D
Measure the resistance between CN211
and of the indoor fan motor connector.
Yes
Measure the resistance of the horizontal vane
motor coil.
Refer to 9-5.
Replace the varistor (NR11) and fuse (F11).
Are 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 (-) of the indoor
fan motor connector. 1, 2
Is the resistance 1MΩ
or more?
Replace the fuse (F11). 3
Measure the resistance of cement
resistor R111 on the indoor electronic
control P.C. board.
R111
CN211
3
Yes
No
No
Yes
1. The fan motor connector's
2. Connect "+" of the tester to fan motor connector's
wire, and "-" to
measured properly.
3. Please replace the fuse after removing the indoor terminal
P.C. board from the electrical box.
No
Replace the fuse (F11) and the indoor fan motor. 3
Yes
Is the resistance
approximately 4Ω?
Yes
Replace the indoor electronic control P.C. board.
31
Short circuit:
Replace the indoor fan motor.
Short circuit:
Replace the horizontal vane motor and the indoor
electronic control P.C. board.
lead wire is red, whereas
lead wire, otherwise the resistance cannot be
No
Replace the indoor electronic control P.C. board
and the indoor fan motor.
is black.
lead