Check Of Indoor Fan Motor; Check Of Remote Controller And Receiver P.c. Board - Mitsubishi Electric MCFH-13NV-E3 Service Manual

Check of indoor fan motor

A
Indoor fan does not operate.
No
Are lead wires connected?
Reconnect 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.

Check of remote controller and receiver P.C. board

B
Indoor unit operates by pressing the EMERGENCY OPERATION switch, but does not operate with the remote
controller.
WCheck if the remote controller is exclusive for this air conditioner.
Switch on the remote controller.
Is LCD display on the remote
controller visible?
Yes
Remove the batteries and then set them back.
Check if the unit operates with the remote controller.
Does the unit operate with remote controller?
Yes
OK
Is noise heard from radio?
Yes
Are there any fluorescent lights
of inverter or rapid-start type
within the range of 1m?
No
Turn ON the power supply.
Measure the voltage between receiver P.C. board connector No.2(+) and No.1 when the remote controller button is pressed.
Is the voltage approx. 4V DC?
No
(5V DC or 0V DC)
Replace the receiver P.C. board.
Turn OFF the power supply.
Check connector (Fan motor) visually.
Yes
Is resistance 0 (short circuit) or ∞ (open circuit)?
Yes ( 0 or ∞ )
Repair the indoor fan motor.
No
Replace the batteries.(see page 26.)
(not clear)
No
Turn on a radio to AM and press
switch on remote controller.
No
Replace the remote controller.
Yes
Re-install the unit away from lights.
Attach a filter on receiving part.
Yes
Disconnect AUTO RESTART P.C. board from CN104
and short CN104 1 to 5.
Does the unit receive the signal
from the remote controller?
Replace the indoor electronic control P.C. board.
30
Is soldered point normal?
No
(others)
No
Yes
No
Yes
Resolder it.
Replace the indoor electronic control
P.C. board.
Replace the auto restart P.C. board.