50
OCH670
Diagnosis flow
Cause
Inspection method and
troubleshooting
Symptoms: Nothing is displayed on the remote controller
3
LED display of the indoor
controller board
LED1 :
LED2 : or
LED3 : —
10 V DC to 16 V DC?
YES
NO
Lighting
Blinking
Lighting
Blinking
Check the voltage of the
terminal block (TB6) of
the remote controller.
Check the status of the LED2
after disconnecting the remote
controller wire from the terminal
block (TB5) of the indoor unit.
• Defective
remote controller
• Replace the
remote controller.
• Breaking or poor
contact of the remote
controller wire
• Check if there is breaking
or poor contact of the
remote controller wire.
Check the voltage of the
terminal block (TB5)
connecting the remote
controller wire.
If it is not between DC 10 V
and 16 V DC, the indoor
controller board must be
defective.
• The remote controller
wire short-circuits
• Check if the remote
controller wire is
short-circuited.
• Defective indoor
controller board
• Replace the indoor
controller board.
Check the status
of the LED2.
Check the status
of the LED2.