Mitsubishi Electric MSZ-AP25VG-E1 Service Manual page 39

MSZ-AP60/71VG
MSZ-AP60/71VGK
Turn OFF the power supply.
Remove indoor fan motor connector CN211 and vane
motor connector CN151 and CN152 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.
Terminal Indoor electronic
P.C. board control P.C. board
Fuse (F11)
LD201(T)
Varistor (NR11)
OBH788C
Measure the resistance between CN211
and of the indoor fan motor connector.
Yes
Measure the resistance of the horizontal vane
motor coil.
Refer to 10-5.
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
fan motor connector.
Is the resistance 1 MΩ or more?
Replace the fuse (F11). 3
Measure the resistance of cement
resistor R111 on the indoor electronic
control P.C. board.
LD201(M)
R111
Yes
No
No
Yes
1. The fan motor connector's
2. Connect "+" of the tester to fan motor connector's
wire, and "-" to
(+) and (-) of the indoor
measured properly.
1, 2
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 4 Ω?
Yes
Replace the indoor electronic control P.C. board.
39
Short/open circuit:
Replace the indoor fan motor.
Short/open 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