Mitsubishi Electric Mr.Slim MSY-D30NA, Service Manual

Page: 22 / 214

22
9-3. INSTRUCTION OF TROUBLESHOOTING
Indoor unit oper-
ates.
Outdoor unit
does not operate.
If blinking of OPERATION INDI-
CATOR lamp cannot be checked,
it can be checked with failure
mode recall function.
Indoor unit operates.
Outdoor unit does
not operate normally.
Indoor unit does
not receive the
signal from re-
mote controller.
OPERATION INDICATOR
lamp on the indoor unit is
fl ashing on and off.
Outdoor unit
operates only
in Test Run
operation. Outdoor unit
does not
operate even
in Test Run
operation.
Unit does not
operate normal
operation in
COOL or HEAT
mode.
Indoor unit
operates, when
EMERGENCY
OPERATION
switch is pressed. Indoor unit does
not operate, when
EMERGENCY
OPERATION
switch is pressed.
Check room
temperature
thermistor.
Refer to 8-7.
"Test point
diagram and
voltage". Refer to "How
to check
inverter/com-
pressor". Refer to
"Check of R.V.
coil". Refer to 9-6.
"Check of remote
controller and
receiver P.C.
board".
1. Check indoor/out-
door connecting wire.
(Check if the power is
supplied to the indoor
unit.)
2. Refer to 9-6. "Check
of indoor electronic
control P.C. board and
indoor fan motor".
Left lamp
Flash on and
off at 0.5-sec-
ond intervals
Cause:
Indoor/Outdoor
unit
• Miswiring or
trouble of
serial signal
Left lamp
2-time fl ash
Cause:
Indoor unit
• Trouble of
room tem-
perature /
indoor coil
thermistor
Left lamp
3-time fl ash
Cause:
Indoor unit
• Trouble of
indoor fan
motor
Left lamp
4-time fl ash
Cause:
Indoor unit
• Trouble
of indoor
unit control
system
Left lamp
5-time fl ash
Cause:
Outdoor unit
• Outdoor
power
system
abnormality
Left lamp
6-time fl ash
Cause:
Outdoor unit
• Trouble of
thermistor in
outdoor unit
Left lamp
7-time fl ash
Cause:
Outdoor unit
• Trouble of
outdoor con-
trol system
Left lamp
14-time fl ash
Cause:
Outdoor unit
• Other ab-
normality
Start
Refer to 9-6.
"How to
check miswir-
ing and serial
signal error".
Check room
temperature
thermistor
and indoor
coil thermis-
tor. Refer
to 9-7."Test
point diagram
and voltage".
Refer to 9-6.
"Check of
indoor fan
motor".
Replace the
indoor elec-
tronic control
P.C. board.
Refer to "How
to check
inverter/com-
pressor".
Refer to
"Check of
outdoor
thermistors".
Check "Flow
chart of the
detailed
outdoor unit
failure mode
recall func-
tion."
"Test Run operation" means the
operation within 30 minutes after
EMERGENCY OPERATION
switch is pressed.
Refer to outdoor unit service manual.
Replace the
inverter P.C.
board or the
outdoor elec-
tronic control
P.C. board.