84
Yes
Yes
Check of indoor fan motor
R
Check of remote controller and receiver P.C. board
S
When OPERATION INDICATOR lamp flashes 3-time.
Indoor fan doesn’t operate.
W
Check if the remote controller is exclusive for this air conditioner.
Replace the batteries.(Refer to page 66.)
Turn on a radio to AM and press switch on
the remote controller.
Is noise heard from radio?
Are there any fluorescent lights of
inverter or rapid-start type within
the range of 1m?
Measure the voltage between receiver P.C. board connector CN301 No.2(+)and No.3(-) when the remote controller
button is pressed.
Is the voltage approx. 4V DC?
Replace the indoor electronic control
P.C. board.
Replace the receiver P.C. board.
Replace the remote controller.
• Reinstall the unit away from lights.
• Attach a filter on receiving part.
Switch on the remote controller.
Is LCD display on the remote con-
troller visible?
Remove batteries, then set them back and
press the RESET button. Check if the unit
operates with the remote controller.
Yes
Does the unit operate with the
remote controller?
Yes
OK
No
(not clear)
Yes
No
No
No(5V or 0V DC)
No
Repair the indoor fan motor.
Disconnect lead wires from connector CN211 on the indoor electronic control P.C. board.
Measure resistance between lead wires No.1 and No.4 and then No.1 and No.3.
Are lead wires connected?
Reconnect the lead wires.
Is soldering point of the connector correctly soldered?
Resolder it.
Is resistance 0 (short circuit) or
∞
(open circuit)?
Yes ( 0 or
∞
)
No
(others)
Yes
No
Yes
No
Turn OFF the power supply.
Check connector CN211 visually.
Insert screwdriver into air outlet to rotate indoor
fan motor slowly for 1 revolution or over, and
measure voltage No.2(+) and No.3(-) at CN121.
Replace the indoor electronic control P.C. board.
Does voltage repeat 0V DC and 5V DC?
Yes
No
Indoor unit operates by pressing the EMERGENCY OPERATION switch, but doesn’t operate with the remote controller.
MSZ-G20SV -
MUZ-G20SV -
E1
E1
on page 84 ~ on page 89
R
AA
OB245--3qxp 02.10.22 4:15 PM Page 84