Mitsubishi Electric PAC-IF012B Technical Manual page 43

Abnormal point and detection method
Error Code
Interface unit/outdoor unit
communication error (Signal receiving
error)
1 Abnormal if Interface controller board
cannot receive any signal normally for 6
minutes after turning the power on.
2 Abnormal if Interface controller board
E6
cannot receive any signal normally for 3
minutes.
Interface unit/outdoor unit
communication error (Signal receiving
error)
(Outdoor unit)
Abnormal if outdoor controller circuit board
could not receive anything normally for 3
E8 minutes.
Interface unit/outdoor unit
communication error (Transmitting
error) (Outdoor unit)
(1) Abnormal if "0" receiving is detected
30 times continuously though outdoor
controller circuit board has transmitted
"1".
E9
(2) Abnormal if outdoor controller
circuit board could not fi nd blank of
transmission path for 3 minutes.
Non defi ned error code
This code is displayed when non defi ned
error code is received.
EF
Serial communication error
Abnormal if serial communication between
outdoor controller circuit board and outdoor
power circuit board is defective.
Ed
Case
1 Contact failure, short circuit
or, miswiring (converse wiring)
of Interface unit/outdoor unit
connecting wire
2 Defective transmitting receiving
circuit of Interface controller
board
3 Defective transmitting receiving
circuit of Interface controller
board
4 Noise has entered into Interface
unit/outdoor unit connecting
wire.
1 Contact failure of Interface unit/
outdoor unit connecting wire
2 Defective communication circuit
of outdoor controller circuit
board
3 Defective communication circuit
of Interface controller board
4 Noise has entered into Interface
unit/outdoor unit connecting
wire.
1 Interface unit/outdoor unit
connecting wire has contact
failure.
2 Defective communication circuit
of outdoor controller circuit
board
3 Noise has entered power
supply.
4 Noise has entered Interface
unit/outdoor unit connecting
wire.
1 Noise has entered transmission
wire of remote controller.
2 Noise has entered Interface
unit/outdoor unit connecting
wire.
1 Wire disconnection or contact
failure of connector CN2
between the outdoor controller
circuit board and the outdoor
power circuit board
2 Wire disconnection or contact
failure of connector CN4
between the outdoor controller
circuit board and the outdoor
power circuit board
3 Defective communication circuit
of outdoor power circuit board
4 Defective communication circuit
of outdoor controller circuit board
for outdoor power circuit board
43
Judgment and action
* Check LED display on the outdoor control
circuit board. (Connect A-control service tool,
PAC-SK52ST.)
1 Check disconnection or looseness of
Interface unit/outdoor unit connecting wire of
Interface unit or outdoor unit.
2~4 Turn the power off, and on again to
check. If abnormality generates again,
replace Interface controller board or
outdoor controller circuit board.
1 Check disconnection or looseness of
Interface unit/outdoor unit connecting wire of
Interface unit or outdoor unit.
2~4 Turn the power off, and on again to
check. Replace Interface controller
board or outdoor controller circuit board
if abnormality is displayed again.
1 Check disconnection or looseness of
Interface unit/outdoor unit connecting wire.
2~4 Turn the power off, and on again to
check. Replace outdoor controller circuit
board if abnormality is displayed again.
12 Turn the power off, and on again to check.
Replace Interface controller board
or outdoor controller circuit board if
abnormality is displayed again.
12 Check connection of each connector CN2
and CN4 between the outdoor controller
circuit board and the outdoor power circuit
board.
3 Replace outdoor power circuit board.
4 Replace outdoor controller circuit board.