Daikin E Series, Service Manual

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SiAU18-715 Troubleshooting for Outdoor Unit
Troubleshooting 381
7.22 Malfunction of Transmission between Inverter and
Control PCB
Remote
Controller
Display
LC
Applicable
Models AII outdoor unit models
Method of
Malfunction
Detection Check the communication state between inverter PCB and control PCB by micro-computer.
Malfunction
Decision
Conditions When the correct communication is not conducted in certain period.
Supposed
Causes
„
Malfunction of connection between the inverter microcomputer and outdoor control
microcomputer
„
Defect of outdoor unit PCB
„
Defect of noise filter
„
External factor (Noise etc.)
Troubleshooting
Caution
Be sure to turn off power switch before connect or disconnect connector,
or parts damage may be occurred.
The
microcomputer
monitor (green) on the
outdoor unit PC board
(A1P) is blinking.
Check the noise filter
(A3P) for disconnection,
and check the power
supply wiring.
(Q0571)
Replace outdoor unit PC
board (A1P).
YES
The
voltage
between red and
white of X1A on the
inverter unit is the
power supply
voltage.
Replace outdoor unit PC
board (A1P).
↓
When the LC malfunction
occur again, replace
control PC board.
YES
NO
NO