33
Check of indoor electronic control P.C. board and indoor fan motor
C
MS-CP13VA
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 Emergency operation
switch?
Yes
No
Measure the resistance of indoor fan
motor.
Refer to 9-5.
Short circuit:
Replace the indoor fan motor.
Turn OFF the power supply.
Check both “parts side” and “pattern
side” of the indoor power 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
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 tester 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 V to 13 V DC between
12 V (+) and GND (-) of the indoor
electronic control P.C. board?
Is the 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 discon-
nection.
No
Indoor electronic control
P.C. board
GND
CN10A
12 V DC
5 V DC
Indoor power P.C. board
CN211
R111
Is the resistance of
resistor (R111)
approximately 4 Ω?
Yes
OBH782A