Mitsubishi Electric MSZ-A09NA Service Manual page 19

B Check of remote controller and indoor electronic control P.C. board
Check if the remote controller is exclusive for this air conditioner.
Press OPERATE/STOP (ON/OFF)
button on the remote controller.
Is LCD display on the remote controller
visible?
Yes
Remove the batteries, then set them back
and press RESET button. (Refer to 8-1.4.)
Check if the unit operates with the remote
controller.
Does the unit operate with the remote
controller?
Yes
OK
MSZ-A24NA MSY-A24NA
MSZ-GA24NA MSY-GA24NA
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. 4 VDC?
Replace the receiver P.C. board.
Replace the batteries. (Refer to 8-1.4.)
No
(Not clear)
Turn ON a radio to AM and press OP-
ERATE/STOP (ON/OFF) button on the
No
remote controller.
Is noise heard from radio?
Yes
Are there any fl uorescent lights of
inverter or rapid-start type within the
range of 3.28 ft.?
No
Yes
No (5 or 0 VDC)
No
Yes
MSZ-A09/12/15/17NA
MSY-A15/17NA
Replace the indoor electronic control
P.C. board.
19
Replace the remote controller.
• Reinstall the unit away from lights.
• Attach a fi lter on receiving part.