59
Yes
Yes
Check of indoor fan motor
A
Check of remote controller and receiver P.C. board
B
When OPERATION INDICATOR lamp flashes 3-time.
Indoor fan motor doesn’t operate.
Repair or replace 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.2(MSH-18/24RV).
No.3 and No.4 and then No.1 and No.4(MSH-30RV).
Are lead wires connected?
Re-connect the lead wires.
Is soldered point normal?
Re-solder it.
Is resistance 0 (short circuit) or
∞
(open circuit)?
Indoor unit operates by pressing the EMERGENCY OPERATION switch, but doesn’t operate with the remote con-
troller.
Replace the batteries.(Refer to page 52.)
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 No.2(+) and No.1 (MSH-18/24RV) / CN301
No.1(+) and No.3(-) (MSH-30RV) 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.
●
Re-install the unit away from lights.
●
Attach a filter on receiving part.
Yes ( 0 or
∞
)
No
(others)
Yes
No
Yes
No
Switch on the remote controller.
Is LCD display on the the remote
controller visible?
Remove the 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
Turn OFF the power supply.
Check connector CN211 visually.
w
Check if the remote controller is exclusive for this air conditioner.
Turn ON the power supply. Stop it if the unit operate.
Insert screwdriver into air outlet to rotate indoor fan
motor slowly for 1 revolution or over, and measure
voltage between No.2(+) and No.3(-) on CN121.
Replace the indoor electronic control P.C. board.
Does voltage repeat 0V DC and 5V DC?
Yes
No
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