20
A Check of indoor fan motor
10-6. TROUBLESHOOTING FLOW
10-5. TROUBLE CRITERION OF MAIN PARTS
Part name
Check method and criterion
Figure
Room temperature
thermistor (RT11)
Indoor coil thermistor
(RT12)
Measure the resistance with a tester.
Refer to 10-7. "Test point diagram and voltage", "1. Indoor electronic control
P.C. board", for the chart of thermistor.
Indoor fan motor (MF)
INNER FUSE
145 °C CUT OFF
Measure the resistance with a tester.
(Part temperature 10 ~ 30 °C)
Color of the lead wire
Normal
WHT-BLK
334
Ω
~ 362
Ω
BLK-RED
370
Ω
~ 402
Ω
MAIN
AUX.
BLK
RED WHT
FUSE
Horizontal vane motor
(MV)
Measure the resistance between the terminals with a tester.
(Temperature: 10 - 30°C)
Color of the lead wire
Normal
RED-BLK
223
Ω
~ 268
Ω
BLK
BLK
RED
BLK
BLK
ROTOR
CN211
Indoor power P.C.board
Fuse (F11)
Indoor terminal
P.C.board
Varistor
(NR11)
CN121
Are soldered points of the
connector correctly soldered to
the indoor power P.C. board?
Is the resistance 0 (short circuit) or
(open circuit)?
Yes ( 0 or
)
Yes
Pay enough attention to the high voltage on the
fan motor connector.
No
Yes
No
Turn OFF the power supply.
Check connector CN211 visually.
Disconnect lead wires from connector CN211 on indoor power P.C. board.
Measure the resistance between lead wires No.1 and No.4 and then No.4 and No.7.
Turn ON the power supply. Stop it if the unit operates.
Insert screwdriver into air outlet to rotate indoor fan
motor slowly for 1 revolution or over, and measure the
voltage No.2(+) and No.1(-) on CN121.
No
(others)
Replace the indoor power/terminal P.C. board
and the indoor control P.C. board.
Does the voltage repeat 0 VDC and 5 VDC?
Yes
No
Are lead wires connected?
Reconnect the lead wires.
Resolder it.
Replace the indoor fan motor.
OBH621
