Check Of Indoor Fan Motor; Check Of Remote Controller And Receiver P.c. Board - Mitsubishi Electric MSC-07RV 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 CN211 on indoor electronic control P.C. board.
Measure resistance between lead wires No.1 and No.3 and then No.2 and No.3.

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 the remote controller is exclusive for this air conditioner.
wReplace the receiver P.C. board together with the indoor control P.C. board.
Switch on the remote controller.
Is LCD display on the remote con-
troller visible?
Yes
Remove batteries and then set them back.
Check if the unit operates with the remote
controller.
Does the unit operate with the
remote controller?
Yes
OK
Turn OFF the power supply.
Check connector CN211 visually.
Yes
Is resistance 0 (short circuit) or ∞ (open circuit)?
Repair the indoor fan motor.
No
Replace the batteries.(See page 122.)
(not clear)
No
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?
Replace the indoor electronic control P.C.
board with receiver.
Is soldered point normal?
Yes ( 0 or ∞ ) (others)
No
Yes
Yes
No
132
Yes
Resolder it.
Replace the indoor electronic con-
trol P.C. board.
No
Replace the remote controller.
• Re-install the unit away from lights.
• Attach a filter on receiving part.
No