Outdoor Communication Signal Error (Forward Transfer Signal Error) - Fujitsu AB A30LBT Series Service Instruction

Trouble shooting 12
INDOOR UNIT Error Method:
Outdoor Communication Signal Error
(Forward Transfer Signal Error)
Detective Actuators:
Indoor Unit Controller PCB Circuit
Forecast of Cause:
1. Connection failure 2. External cause 3. Controller PCB failure
Check Point 1-1 : Reset the power
Does Error indication reappear?
YES
Check Point 2 : Check Connection
Check any loose or removed connection line of
Indoor unit and Outdoor unit.
>> If there is an abnormal condition, correct it by
referring to Installation Manual or Data &
Technical Manual.
Check connection between Indoor Unit Controller PCB
and Filter PCB.
(If there is loose connector or open cable)
OK
Check Point 3 : Check the voltage of power supply
Check the voltage of power supply.
>> Check if AC198 - 264V appears at Outdoor Unit Terminal L - N.
OK
Check Point 4 : Check Serial Signal (Forward Transfer Signal)
Check Serial Signal (Forward Transfer Signal)
>> Check if Indicated value swings between AC70V and AC130V
at Outdoor Unit Terminal 2 - 3.
>> If it is abnormal, Controller PCB is failure. >> Replace Controller PCB.
N
WHITE
L
BLACK
3
RED
2
WHITE
1
BLACK
Indicate or Display:
Refer to error code table.
Detective details:
When the outdoor unit cannot receive the serial signal from Indoor unit
more than 10seconds.
NO
Check Point 1-2 : Check external cause such as noise
Check the complete insulation of the grounding.
Check if there is any equipment that causes harmonic
wave near the power cable (Neon light bulb or any
electronic equipment which causes harmonic wave).
+
-
02-16
AC
AC