Mitsubishi Electric MCF-C13UV-E1 Service Manual page 34

Indoor fan does not operate.
Check of indoor fan motor
A
No
Are lead wires connected?
Re-connect the lead
wires.
Disconnect lead wires from connector (Fan motor)on indoor electronic control P.C. board.
Measure resistance between lead wires No.1 and No.4 and then No.3 and No.4 of the fan motor.
Indoor unit operates by pressing the EMERGENCY OPERATION switch, but does not operate with the remote con-
troller.
Check of remote controller and receiver P.C. board
B
w Check if the remote controller is exclusive for this air conditioner.
Switch on the remote controller
Is LCD display on remote
controller visible?
Remove batteries, then set them back and press
the RESET button. Check if the unit operates with
remote controller.
Does the unit operate with remote controller?
OK
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 when remote controller button is pressed.
Is the voltage approx. 4V DC?
Replace the receiver P.C. board.
Turn OFF power supply.
Check connector (Fan motor) visually.
Yes
Is resistance 0 (short circuit) or ∞ (open circuit)?
Replace the indoor fan motor.
No
(not clear)
Yes
Yes
Turn on a radio to AM and press
switch on remote controller.
No
Yes
Yes
No
No
Yes
No
(5V DC or 0V DC)
Yes ( 0 or ∞ )
Replace the batteries.(Refer to page 31.)
No
Replace the remote controller.
Re-install the unit away from lights.
Attach a filter on receiving part.
Replace the indoor
electronic control P.C. board.
34
Is soldered point of the connector
correctly soldered?
Yes
Replace the indoor electronic control
P.C. board.
No
(others)
No
Re-solder it.