Mitsubishi Electric MSZ-D30NA Service Manual page 26

B Check of remote controller and receiver P.C. board
* Check 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, then set them back
and press RESET button. (Refer to 9-1.4.)
Check if the unit operates with the remote
controller.
Does the unit operate with the remote
controller?
Yes
OK
OBH501D
Replace the batteries. (Refer to 9-1.4.)
No
(Not clear)
Turn ON a radio to AM and press switch
No ON the remote controller.
Is noise heard from radio?
Yes
Are there any fluorescent lights of
inverter or rapid-start type within the
range of 3.28 ft.?
No
Measure the voltage between receiver P.C. board
connector CN301 (+) and
controller button is pressed.
Is the voltage approximately 4 V DC?
No (5 or 0 V DC)
Replace the receiver P.C. board.
No
Yes
(-) when the remote
Yes
26
Replace the remote controller.
• Reinstall the unit away from lights.
• Attach a filter on receiving part.
Replace the remote controller.