Mitsubishi Electric MXZ-2D33VA-E1 Service Manual page 46

Upper or left lamp of
Abnormal point
OPERATION INDICATOR
(Failure mode/protection)
lamp (Indoor unit)
Communication error
11-time flash
between P.C. boards
Current sensor
Zero cross detecting circuit
Converter
Bus-bar voltage
(1)
Bus-bar voltage
(2)
Even if this protection stop is
performed continuously three
times, it does not mean the
abnormality in outdoor power
system.
15-time flash LEV and drain pump
NOTE: Blinking patterns of this mode differ from the ones of "Troubleshooting check table" (11-4).
OBH626H
LED indication
(Outdoor P.C. board) Condition
LED 1 LED 2
Communication error occurs
Lighted 6 times
between the electronic control P.C.
board and power board for more
than 10 seconds.
The communication between boards
protection cut-out operates 2
consecutive times.
Lighted 7 times A short or open circuit is detected in
the current sensor during compressor
operating.
Current sensor protection cut-out
operates 2 consecutive times.
5 times Not
Zero cross signal cannot be detected
lighted
while the compressor is operating.
The protection cut-out of the zero cross
detecting circuit operates 10
consecutive times.
5 times
Not
A failure is detected in the operation
of the converter during operation.
lighted
5 times
Not
The bus-bar voltage exceeds 400 V or
lighted falls to 200 V or below during
compressor operating.
6 times
Not
The bus-bar voltage exceeds
lighted
400 V (MXZ-3D54/3D68/4D72VA
MXZ-3D54VA2)
430 V (MXZ-4D83/5D102VA)
or falls to 50V or below during
compressor operating.
Lighted Lighted
The indoor unit detects an abnormality
in the LEV and drain pump.
126
Indoor/outdoor
Remedy
unit failure mode
recall function
Check the connecting
wire between the outdoor
control P.C. board and
the power P.C. board.
Replace the power P.C.
board.
Check the connecting
wire between the control
P.C. board, the noise
filter P.C. board and
the power P.C. board.
Check the voltage of the
power supply.
power P.C.
board.
Check the voltage of the
power supply.
control P.C. board.
Refer to 11-6. "Check
of LEV".
Check the drain pump of
the indoor unit.