MLZ-KP Service Manual

26
NOTE: When the indoor unit has started operation and the above failures are detected (the first detection after the power ON),
the indoor electronic control P.C. board turns OFF the indoor fan motor with OPERATION INDICATOR lamp flashing.
Left lamp flashes.
7-time flash
2.5-second OFF
Left lamp flashes.
14-time flash or more
2.5-second OFF
No.
1
3
6
7
SymptomOperation indicator lamp Condition
Remedy
Left lamp flashes.
0.5-second ON
0.5-second OFF
Miswiring
or serial
signal
Outdoor
power
system
Outdoor
thermistors
Outdoor
control
system
Indoor coil
thermistor
When the serial signal from the outdoor unit is
not received for a maximum of 6 minutes.
The compressor stops 3 times consecutively
for over current protection or start-up failure
protection within 1 minute after start-up.
When the outdoor thermistors short or open
circuit during the compressor operation.
When it cannot properly read data in the
nonvolatile memory of the inverter P.C. board
or of the outdoor electronic control P.C. board.
5HIHUWR&KHFNRIRXWGRRU
WKHUPLVWRU
Refer to outdoor unit service
manual.
5HIHUWR&KHFNRILQYHUWHU 
FRPSUHVVRU
Refer to outdoor unit service
manual.
&KHFNWKHVWRSYDOYH
5HSODFHWKHLQYHUWHU3&
board or the outdoor electronic
control P.C. board.
Refer to outdoor unit service
manual.
5HIHUWR+RZWRFKHFN
miswiring and serial signal
 HUURU
4
Indoor fan
motor
8
Abnormal
point
Room
temperat-
ure
thermistor
Left lamp flashes.
2-time flash
2.5-second OFF
When the indoor coil or the room temperature
thermistor is shorts or opens circuit.
5HIHUWRWKHFKDUDFWHULVWLFVRI
indoor coil thermistor, and the
room temperature thermistor
RQ
Left lamp flashes.
3-time flash
2.5-second OFF
:KHQWKHURWDWLRQDOIUHTXHQF\IHHGEDFN
signal is not emitted during the indoor fan
operation.
5HIHUWR&KHFNRI
LQGRRUIDQPRWRU
Indoor unit
and outdoor
unit do not
operate.
Indoor unit
and outdoor
unit do not
operate.
Left lamp flashes.
5-time flash
2.5-second OFF
Left lamp flashes.
6-time flash
2.5-second OFF
Indoor unit
and outdoor
unit do not
operate.
Indoor unit
and outdoor
unit do not
operate.
Indoor unit
and outdoor
unit do not
operate.
Other
abnormality
An abnormality other than above mentioned is
detected.
&KHFNWKHDEQRUPDOLW\LQ
detail using the failure mode
recall function.
Refer to outdoor unit service
manual.
Indoor unit
and outdoor
unit do not
operate.
Indoor unit
and outdoor
unit do not
operate.

5
Left lamp flashes.
4-time flash
2.5-second OFF
Indoor
control
system
When it cannot properly read data in the
nonvolatile memory of the indoor electronic
control P.C. board.
Indoor unit
and outdoor
unit do not
operate.
5HSODFHWKHLQGRRUHOHFWURQLF
control P.C. board.
2
)ORDWVHQVRULVRSHQ
)ORDWVHQVRUGHWHFWVDEQRUPDOZDWHUOHYHO
&KHFNWKHIORDWVHQVRU
characteristics.
&KHFNWKHGUDLQSXPS
&KHFNWKHGUDLQSLSH
&KHFNWKHFRQQHFWRUVRIIORDW
sensor and the drain pump.
5HIHUWR&KHFNRIIORDW
VHQVRU
Indoor unit
and outdoor
unit do not
operate.
Left lamp flashes.
WLPHIODVK
2.5-second OFF
Drain
pump
9-4. TROUBLESHOOTING CHECK TABLE
NOTE: Before taking measures, make sure that the symptom reappears for accurate troubleshooting.
OPERATION INDICATOR
Not lit
Blinking
Lit
· Flashing of OPERATION INDICATOR lamp (left-hand side lamp) indicates
abnormalities.
Self check table
OBH802