Mitsubishi MSZ-A09YV-E1, MSZ-A12YV-E1 Service Manual

SERVICE MANUAL

SPLIT-TYPE, HEAT PUMP AIR CONDITIONERS

Wireless type
Models

E1

E1

(WH)

(WH)

MSZ-A09YV ­MSZ-A12YV -

No. OB327

Indication of model name

MSZ-A09YV ­MSZ-A12YV -

NOTE:

This service manual describes technical data of the indoor units.

•Refer to the service manual OB328 when MSZ-A09YV- or MSZ-A12YV- is connected
with MUZ-A09YV- , MUZ-A12YV- , MUZ-A09YVH- or MUZ-A12YVH- .

•Refer to the service manual OB319 when MSZ-A09YV- or MSZ-A12YV- is connected
with MXZ-A18WV- , MXZ-A26WV- or MXZ-A32WV- as multi system units.

E1

E1

CONTENTS

1. PART NAMES AND FUNCTIONS······················2

2. SPECIFICATION·················································4

3. NOISE CRITERIA CURVES·······························5

4. OUTLINES AND DIMENSIONS·························6

5. WIRING DIAGRAM ············································7

6. REFRIGERANT SYSTEM DIAGRAM················7

7. SERVICE FUNCTIONS ······································8

8. TROUBLESHOOTING······································10

9. DISASSEMBLY INSTRUCTIONS ····················19

10. PARTS LIST······················································21

11. OPTIONAL PARTS···········································23

E1E1

E1E1E1E1

E1E1

E1E1E1

1

1
2
3
4
5
6
7

Installation plate
Installation plate fixing screw 4 o 25 mm
Remote controller holder
Fixing screw for 3 3.5 o 1.6 mm (Black)
Battery (AAA) for remote controller
Wireless remote controller
Felt tape (Used for left or left-rear piping)

MSZ-A09YV -

E1

MSZ-A12YV -

E1

1
5
1
2
2
1
1

PART NAMES AND FUNCTIONS

INDOOR UNIT

MSZ-A09YV ­MSZ-A12YV -

Air cleaning filter
(white bellows type)

Heat exchanger

Catechin air filter
(With deodorizer)

Air outlet

Vertical vanes
Line flow fan

Horizontal vane

Operation section

(When the front panel is opened)

E1

E1

Panel

Front panel
Air inlet

to Breaker

Power supply cord

Remote control
receiving section

Remote controller

Display section

ACCESSORIES

INDOOR UNIT

Emergency operation switch

Operation indicator lamp

Remote control
receiving section

2

ON/OFF

TOO

COOL

PM

AM

TOO

WARM

ON/OFF

FAN

TOO

WARM

TOO

COOL

VANE

MODE

ECONO COOL

STOP

START

HR.

MIN.

AMPM

CLOCK

˚C

AM

RESET CLOCK

I FEEL

COOL

DRY

AUTO

HEAT

Open the front lid.

Signal transmitting section

Operation display section

OPERATE /STOP
(ON /OFF) button

TEMPERATURE buttons

OPERATION SELECT button

FAN SPEED CONTROL button

OFF-TIMER button

HR. button

MIN. button

(TIME SET button)

ON-TIMER button

RESET button

ECONO COOL button

VANE CONTROL button

CLOCK SET button

Indication of remote controller model

MSZ-A09YV ­MSZ-A12YV -

E1

E1

3

1.5+ 440V
250V 3.15A

93:5A 250V

MSBPC20 12V 250"

ERZV10D471

S201DH1Y

5P

JM1aN-ZTMP-DC12V

136:i3: 2A

INDOOR UNIT

Item

Model

Indoor fan capacitor
Fuse
Thermal fuse
Vane motor
Varistor
Solid state relay
Terminal block
Contactor
Indoor fan motor thermal fuse

MSZ-A09YV -

E1

MSZ-A12YV -

E1

(C11)

(F11)

(F12)

(MV)

(NR11)

(SR141)

(TB)

(52C)

2

MSZ-A09YV -

E1

MSZ-A12YV -

E1

Indoor model

Function

Power supply

Single phase

230V,50Hz

10

0.17
35
—

0.17

RC4V19-LA

WHT-BLK 413
BLK-RED 334
815O278O244

9
5

3
10
10
10

KG04A

Cooling

504/360

W

/222

W

88

37/29W/21

W

1,010/770W/540

W

Heating

564/402

W

/246

W

94

38/30W/21

W

1,110/840W/580

W

Single phase

230V,50Hz

10

0.19
40
—

0.19

RC4V19-KA

WHT-BLK 316
BLK-RED 299
815O278O244

10

5

3
10
10
10

KG04A

Cooling

630/462

W

/288

W

95

39/31W/22

W

1,030/800W/570

W

Heating

642/474W/312

W

94

38/30

W

/22

W

1,050/820W/600

W

Air flow

(High/Med.W/LowW)
Power outlet
Running current ✽1
Power input Rated frequency
Auxiliary heater
Power factor ✽1
Fan motor current ✽1
Model
Winding
resistance(at20:)
Dimensions WOHOD
Weight
Air direction
Sound level

(High/Med.W/LowW)
Fan speed(High/Med.W/LowW)
Fan speed regulator
Thermistor RT11(at25:)
Thermistor RT12(at25:)
Thermistor RT13(at25:)
Remote controller model

K /h

A
A

W

A(kW)

%

A

"

mm

kg

dB(A)

rpm

k"
k"
k"

Electrical

data

Fan

motor

Special

remarks

Capacity

SPECIFICATION

NOTE : Test conditions are based on ISO 5151

Cooling : Indoor DB27: WB19:

Outdoor DB35: WB 24:

Heating : Indoor DB 20: WB15:

Outdoor DB 7: WB 6:

Refrigerant piping length (one way): 5m
w Reference value

✽1 Measured under rated operating frequency.

Specifications and rating conditions of main electric parts

4

3

90

80

70

60

50

40

30

20

10

63 125 250 500 1000 2000 4000 8000

NC-60

NC-50

NC-40

NC-30

NC-20

NC-70

OCTAVE BAND SOUND PRESSURE LEVEL, dB re 0.0002 MICRO BAR

BAND CENTER FREQUENCIES, Hz

Test conditions,
Cooling : Dry-bulb temperature 27: Wet-bulb temperature 19:

APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE

COOLING

FUNCTION

37
38

SPL(dB(A))

LINE

High

FAN SPEED

HEATING

Heating : Dry-bulb temperature 20: Wet-bulb temperature 15:

NOISE CRITERIA CURVES

MSZ-A09YV -

E1

MSZ-A12YV -

Test conditions,
Cooling : Dry-bulb temperature 27: Wet-bulb temperature 19:

Heating : Dry-bulb temperature 20: Wet-bulb temperature 15:

90

80

70

60

50

40

30

E1

FAN SPEED

High

FUNCTION

COOLING
HEATING

SPL(dB(A))

39
38

LINE

NC-70

NC-60

NC-50

NC-40

NC-30

APPROXIMATE

20

THRESHOLD OF
HEARING FOR
CONTINUOUS

OCTAVE BAND SOUND PRESSURE LEVEL, dB re 0.0002 MICRO BAR

NOISE

10

63 125 250 500 1000 2000 4000 8000

BAND CENTER FREQUENCIES, Hz

INDOORUNIT

WALL

1m

0.8m

MICROPHONE

NC-20

5

4

OUTLINES AND DIMENSIONS

MSZ-A09YV -

INDOOR UNIT

278

60

58

162

Wireless remote controller

E1

81.5

606

783

815

149

19

Power supply cord
Lead to right 1.0m
Lead to left 0.3m

Installation
plate

Indoor unit

81.5

41

30

Air out

242 5

Air in

7 or more

244

326326

Installation plate

Liquid line
Gas line

{

Insulation

90

110

Drain hose
(Connected part O,D)

Insulation

Unit : mm

133.5

231.5

42

2.5

81.5

Wall hole

[6.35-0.5m

[9.52-0.43m

[37 O.D

[21 I.D

[16

[28

4.5

271

[65

MSZ-A12YV -

INDOOR UNIT

278

60

58

162

Wireless remote controller

E1

783

815

606

19

Installation
plate

Indoor
unit

41

149

Power supply cord
Lead to right 1.0m
Lead to left 0.3m

30

Air out

242
Air in

7 or more

244

326326

5

Installation plate

Liquid line
Gas line

{

Insulation

90

110

Drain hose
(Connected part O,D)

Insulation

Unit : mm

161.5161.5

218.5

42

2.5

81.581.5
Wall hole [65

[6.35-0.5m

[9.52-0.43m

[37 O.D

[21 I.D

[16

[28

17.5

258

6

5

SYMBOL

C11

F11
F12

MF

MV

SYMBOL

NR11

RT11
RT12
RT13

SR141

SYMBOL

SR142

T11

TB

52C

NAME
INDOOR FAN CAPACITOR
FUSE (3.15A)
THERMAL FUSE (93:)
INDOOR FAN MOTOR (INNER FUSE)
VANE MOTOR

NAME
VARISTOR
ROOM TEMPERATURE THERMIST OR
INDOOR COIL THERMISTOR (MAIN)
INDOOR COIL THERMISTOR (SUB)
SOLID STATE RELAY

NAME
SOLID STATE RELAY
TRANSFORMER
TERMINAL BLOCK
CONTACTOR

GRN/YLW

BLK
GRY
YLW
BRN
WHT
RED

MF

1
2
3
4
5
6

3

SR141 SR142

5

3

1

C11

RT13
RT12

CN

112

CN
111

CN
121

151

CN

109CN125

CN

1R1

CN

MV

52

32

5

RT11

CN211

NR11

ELECTRONIC CONTROL P.C. BOARD

F11

T11

230V~

BRN

TB

L

3

N

2

RED

WHT

BLU

F12

BLU

BLU

1
2

BLU

1

2

3

CN201

3

4

52C

12V

TO OUTDOOR
UNIT
CONNECTING

L
3
N
2

12V

TO OUTDOOR

FOR MXZ type

UNIT
CONNECTING

REMOTE
CONTROLLER

POWER MONITOR
RECEIVER

SAFETY
DEVICE (FAN)

P.C. BOARD

LD103

GRN

CIRCUIT BREAKER

POWER
SUPPLY
CORD
~/N 230V
50Hz

PE

WIRING DIAGRAM

MSZ-A09YV ­MSZ-A12YV -

INDOOR UNIT

E1

E1

MODELS WIRING DIAGRAM

NOTE:1. About the outdoor side electric wiring refer to the outdoor unit electric wiring diagram for servicing.

2. Use copper conductors only. (For field wiring)

3. Symbols below indicate.

/: Terminal block, : Connector

6

MSZ-A09YV -

INDOOR UNIT

REFRIGERANT SYSTEM DIAGRAM

E1

Refrigerant pipe [9.52
(with heat insulator)

MSZ-A12YV -

INDOOR UNIT

Indoor coil

Indoor
heat
exchanger

Room temperature
thermistor
RT11

Refrigerant flow in cooling
Refrigerant flow in heating

thermistor
RT12(main)

Indoor coil
thermistor
RT13(sub)

Flared connection

Flared connection

Refrigerant pipe
[6.35
(with heat insulator)

Indoor
heat
exchanger

Room temperature
thermistor
RT11

7

Indoor coil
thermistor
RT13(sub)

E1

Refrigerant pipe [9.52
(with heat insulator)

Indoor coil
thermistor
RT12(main)

Flared connection

Flared connection

Refrigerant pipe
[6.35
(with heat insulator)

Unit:mm

7

SERVICE FUNCTIONS

MSZ-A09YV ­MSZ-A12YV -

E1

E1

7-1. TIMER SHORT MODE

For service, set time can be shortened by short circuit of JPG and JPS the electronic control P.C. board.
The time will be shortened as follows. (Refer to page 18.)
Set time : 1-minute ➔ 1-second
Set time : 3-minute ➔ 3-second (It takes 3 minutes for the compressor to start operation. However, the starting time is

shortened by short circuit of JPG and JPS.)

7-2. P.C. BOARD MODIFICATION FOR INDIVIDUAL OPERATION

A maximum of 4 indoor units with wireless remote controllers can be used in a room.
In this case, to operate each indoor unit individually by each remote controller, P.C. boards of remote controller must be
modified according to the number of the indoor unit.

How to modify the remote controller P.C. board

Remove batteries before modification.
The board has a print as shown below :

Remote controller model : KG04A

J2

NOTE : For remodelling, take out

the batteries and press the
OPERATE/STOP(ON/OFF)
button twice or 3 times at
first.
After finish remodelling,
put back the batteries then
press the RESET button.

J1

The P.C. board has the print “J1” and “J2”. Solder “J1” and “J2” according to the number of indoor unit as shown in Table

1.
After modification, press the RESET button.

Table 1

1 unit operation
No. 1 unit
No. 2 unit
No. 3 unit
No. 4 unit

How to set the remote controller exclusively for particular indoor unit.

After you turn the breaker ON, the first remote controller that sends the signal to the indoor unit will be regarded as the remote
controller for the indoor unit.
The indoor unit will only accepts the signal from the remote controller that has been assigned to the indoor unit once they are
set.
The setting will be cancelled if the breaker has turned off, or the power supply has shut down.
Please conduct the above setting once again after the power has restored.

No modification

–
–
–

2 units operation

Same as at left

Solder J1

–
–

3 units operation

Same as at left
Same as at left

Solder J2

–

4 units operation

Same as at left
Same as at left
Same as at left

Solder both J1 and J2

7-3. AUTO RESTART FUNCTION

When the indoor unit is controlled with the remote controller, the operation mode, the set temperature, and the fan speed
are memorized by the indoor electronic control P.C. board. The “AUTO RESTART FUNCTION” sets to work the moment
power has restored after power failure. Then, the unit will restart automatically.
However if the unit is operated in “I FEEL CONTROL” mode before power failure,
the operation is not memorized. In “I FEEL CONTROL” mode, the operation is decided by the initial room temperature.

8

How to release “AUTO RESTART FUNCTION”

JR07

IC101

CN151

SW1

CN112

CN111

CN201

52C

C11

CN211

CN1V1

CN1R1

CN121

1Turn off the main power for the unit.
2Pull out the indoor electronic control P.C. board and the power monitor receiver P.C.board. (Refer to page 19.)
3Solder the Jumper wire to the JR07 on the indoor electronic control P.C.board. (Refer to page 18.)

Operation

1 If the main power (230V AC) has been cut, the operation settings remain.
2 After the power is restored, the unit restarts automatically according to the memory. (However, it takes at least 3 min-

utes for the compressor to start running.)

NOTE:

• The operation settings are memorized when 10 seconds have passed after the indoor unit was operated with the remote

controller.

• If main power is turned OFF or a power failure occurs while AUTO START/STOP timer is active, the timer setting is can-

celled.

• If the unit has been off with the remote controller before power failure, the auto restart function does not works as the

power button of the remote controller is off.

• To prevent breaker off due to the rush of starting current, systematize other home appliance not to turn on at the same

time.

• When some air conditioners are connected to the same supply system, if they are operated before power failure, the

starting current of all the compressors may flow simultaneously at restart.
Therefore, the special counter-measures are required to prevent the main voltage-drop or the rush of the starting current
by adding to the system that allows the units to start one by one.

9

8

RESET button

Housing point

TROUBLESHOOTING

MSZ-A09YV ­MSZ-A12YV -

E1

E1

8-1. Cautions on troubleshooting

1. Before troubleshooting, check the following:

1) Check the power supply voltage.

2) Check the indoor/outdoor connecting wire for mis-wiring.

2. Take care the following during servicing.

1) Before servicing the air conditioner, be sure to first turn off the remote controller to stop the main unit, and then after
confirming the horizontal vane is closed, turn off the breaker and / or disconnect the power plug.

2) Be sure to turn OFF the power supply before removing the front panel, the cabinet, the top panel, and the
electronic control P.C. board.

3) When removing the electronic control P.C. board, hold the edge of the board with care NOT to apply stress on the
components.

4) When connecting or disconnecting the connectors, hold the housing of the connector. DO NOT pull the lead wires.

Lead wiring

3. Troubleshooting procedure

1) First, check if the OPERATION INDICATOR lamp on the indoor unit is flashing on and off to indicate an abnormality.
To make sure, check how many times the abnormality indication is flashing on and off before starting service work.

2) Before servicing check that the connector and terminal are connected properly.

3) If the electronic control P.C. board is supposed to be defective, check the copper foil pattern for disconnection and the

components for bursting and discoloration.

4) When troubleshooting, refer to the flow chart on page 12 and the check table on page 13.

4. How to replace batteries

Weak batteries may cause the remote controller malfunction.
In this case, replace the batteries to operate the remote controller normally.

1 Remove the front lid and insert batteries.

Then reattach the front lid.

Insert the negative pole
of the batteries first.
Check if the polarity of
the batteries are correct.

NOTE : 1. If the RESET button is not pressed, the remote controller may not operate correctly.

2. This remote controller has a circuit to automatically reset the microcomputer when batteries are replaced.
This function is equipped to prevent the microcomputer from malfunctioning due to the voltage drop caused by
the battery replacement.

2 Press the RESET button with tip end of ball point

pen or the like, and then use the remote controller.

10

5. How to install the horizontal vanes

Lighted

Flashing

Operation Indicator

If horizontal vanes are not installed correctly, both of the operation indicator lamps will flash.
In this case, install the horizontal vanes correctly by following the procedures 1 to 6.

NOTE: Before installation of the horizontal vanes, disconnect the power supply plug and/ or turn off the breaker.

Upper vane

Insert this end first.

Lower vane

Insert this end first.

Upper right

The holes on the
insertion ends of
the upper and lower
horizontal vanes
different shapes.

654

Lock.

Stopper

Lock.

Stopper

In.

321

Insert.

Lower right

Lock.

Lock.

In.

In procedures 2,3,5, and 6, lock the stoppers until they click into place.

INFORMATION FOR MULTI SYSTEM AIR CONDITIONER
OUTDOOR UNIT : MXZ series

Multi system air conditioner can connect two or more indoor units with one outdoor unit.

•Unit won’t operate in case the total capacity of indoor units exceeds the capacity of outdoor units. Do not
connect indoor units beyond the outdoor unit capacity.
Operation indicator lamp flashes as shown in the figure below.

•When you try to operate two or more indoor units with one outdoor unit simultaneously, one for the cooling and
the other for heating, the operation mode of the indoor unit that operates earlier is selected. The other indoor
units will start the operation later cannot operate, indicating as shown in the figure below. In this case, please
set all the indoor units to the same operation mode.

•When indoor units starts the operation while the defrosting of outdoor unit is being done, it takes a few min­utes (max. 10 minutes) to blow out the warm air.

•In the heating operation, though indoor unit that does not operate may get warm or the sound of refrigerant
flowing may be heard, they are not malfunction. The reason is that the refrigerant continuously flows into it.

Insert.

11

Start

Indoor unit
operates.
Outdoor unit
doesn't
operate.

Indoor unit
doesn't receive
the signal from
remote controller.

OPERATION INDICATOR
lamp on the indoor unit is
flashing on and off.

Outdoor unit
operates in
only Test Run
operation.

Outdoor unit
doesn't
operate
even in
Test Run
operation.

Indoor unit
operates, when
the EMERGENCY
OPERATION
switch is pressed.

Indoor unit
doesn't operate,
when the
EMERGENCY
OPERATION
switch is pressed.

Check room
temperature
thermistor.
Refer to
"Test point
diagram and
voltage" on
page 18.

Refer to
"Check of
inverter/
compressor".

Refer to B
"Check of
remote controller
and receiver
P.C. board"
on page 15.

1. Check indoor / outdoor
connecting wire.
(Check if the power
is supplied to the
indoor unit.)

2. Refer to C
"Check of indoor
electronic control
P.C. board"
on page 15.

Unit doesn't
operate
normal
operation in
COOL or
HEAT mode.

Refer to
"Check of
R.V. coil".

Left lamp
Flash on and
off at

0.5-second
intervals
Cause:
Indoor/
Outdoor unit

• Mis-wiring

Left lamp
2-time flash
Cause:
Indoor unit

• Trouble of
room temp­ erature/
indoor coil
thermistor

Left lamp
3-time flash
Cause:
Indoor unit

• Trouble of
indoor fan
motor

Left lamp
5-time flash
Cause:
Outdoor unit

• Outdoor
power
system
abnormality

Left lamp
6-time flash
Cause:
Outdoor unit

• Trouble of
thermistor
in outdoor
unit

Left lamp
7-time flash
Cause:
Outdoor unit

• Trouble of
outdoor
control
system

Refer to D
"How to
check of
mis-wiring
(When
outdoor unit
doesn't work)"
on page 16.

Both lamps
(Left and right)
Flash on and off
at 0.5-second
intervals
Cause:
Indoor unit

• The horizontal
vanes are not
installed
correctly.

Refer to E
"Check of
installation of
the horizontal
vanes" on
page 17.

Check room
temperature
thermistor
and indoor
coil thermis­tor.
Refer to
"Test point
diagram and
voltage"
on page 18.

Refer to A
"Check of
indoor fan
motor"
on page 14.

Refer to
"Check of
inverter/
compressor".

Refer to
"Check of
outdoor
thermistor".

Replace the
inverter P.C.
board and
others.

Left lamp
4-time flash
Cause:
Indoor unit

• Trouble of
indoor unit
control
system

Replace the
indoor
electronic
control
P.C. board.

As for outdoor unit, refer to
service manual OB328 or OB319.

8-2. Instruction of troubleshooting

12

1. Troubleshooting check table

Operation Indicator

· Flashing of the OPERATION INDICATOR lamp (on the left or both)
indicates possible abnormalities.

· The OPERATION INDICATOR lamp (on the left) is
lighting during normal operation.

flashing

• The following indication applies regardless of shape of the indicator.

NOTE : Before taking measures, make sure that the symptom reappears for accurate troubleshooting.

Self check table

Abnormal

No.

1

w2

w3

4

5

6

7

8

point

Attachment
of the
horizontal
vane

Mis-Wiring

Indoor coil
thermistor

Room
tempera­ture
thermistor

Indoor fan
motor

Indoor
control
system

Outdoor
power
system

Outdoor
thermistors

Outdoor
control
system

MXZ type

Operation
mode
setting

Both lamps flash at the same time.

0.5-second ON

0.5-second OFF
Left lamp flashes.

0.5-second ON

0.5-second OFF

Left lamp flashes.
2-time flash

2.5-second OFF

Left lamp flashes.
3-time flash

2.5-second OFF

Left lamp flashes.
4-time flash

Left lamp flashes.
5-time flash

2.5-second OFF

Left lamp flashes.
6-time flash

2.5-second OFF

Left lamp flashes.
7-time flash

Operation Indicator

Flashing

Both lamp

Lighted

2.5-second OFF

2.5-second OFF

2.5-second OFF

SymptomOperation indicator lamp Detection method

Indoor unit
and outdoor
unit do not
operate.

Outdoor unit
does not
operate.

Outdoor unit
does not
operate.

Indoor fan
repeats 12
seconds ON
and 3
minutes
OFF.
When the
indoor fan
breaks, the
fan keeps
stopping.

Outdoor unit
does not
operate.

Outdoor unit
does not
operate.

Outdoor unit
does not
operate.

Outdoor unit
does not
operate.

Outdoor unit
operates but
indoor unit
does not
operate.

When the electricity is not conducted to the
safety device (FAN) of the horizontal vane.

3 minutes after power supply turns ON, when
serial signal is not received.

Detect Indoor coil/room temperature
thermistor short or open circuit every 8
seconds during operation.

When rotational frequency feedback signal is
not emit during 12-second indoor fan
operation.

When it cannot properly read data in the
nonvolatile memory of indoor electronic
control P.C. board.

When compressor has stopped due to over
current protection or start-up failure protection
3 times in a row within 5 seconds after start­up.

<Thermistor short>
Thermistors are abnormal when they short
after compressor start-up.
<Thermistor open>
Thermistors are abnormal when they open
after compressor start-up.
However, discharge temperature thermistor is
abnormal when open circuit is detected more
than 10 minutes after compressor start-up.

When it cannot properly read data in the
nonvolatile memory of outdoor electronic
control P.C. board.

When the operation mode of each indoor unit
is differently set to COOL(includes DRY) and
HEAT at same time, the operation mode of
indoor unit that has operated at first has the
priority.

Check point

• Refer to E "Check of
installation of the horizontal
vanes" on page 17.

• Refer to D "How to check
mis-wiring " on page 16.

• Refer to the characteristics of

indoor coil thermistor,
sub indoor coil
thermistor, and room
temperature thermistor on
page 18.

• Refer to A "Check of

indoor fan motor" on page 14.

• Replace the indoor electronic

control P.C. board.

• Refer to "Check of inverter/
compressor".

Refer to service manual
OB328 or OB319.

• Shortage of refrigerant

• Replace the outdoor control

P.C. board.
Refer to "Check of outdoor

thermistor".

Refer to service manual
OB328 or OB319.

• Replace the outdoor

electronic control P.C. board or
inverter P.C. bpard.
Refer to service manual
OB328 or OB319.

• Unify the operation mode.

Refer to service manual
OB319.

NOTE : w When the indoor unit has started operation and the above detection method has detected an abnormality (the first

detection after the power ON), the indoor electronic control P.C. board turns OFF the 52C and the indoor fan motor
with the OPERATION INDICATOR lamp lighting.
When the 52C and the indoor fan motor are turned ON again 3 minutes later and the same abnormality is detected
(a second detection of the above abnormality after the power ON), the indoor electronic control P.C. board turns
OFF the 52C and the indoor fan motor with the OPERATION INDICATOR lamp flashing.
However, the first detection is cleared in case the power is turned OFF after the first detection.

13

2. Trouble criterion of main parts

Part name FigureCheck method and criterion

Indoor fan motor(MF)
INNER FUSE

136i 3: CUT OFF

WHT – BLK

BLK – RED

Abnormal

Open or

short-circuit

Normal

MSZ-A09YV
303 " ~ 329 "
287 " ~ 311 "

MSZ-A12YV
396 " ~ 430 "
320 " ~ 348 "

Measure the resistance with a tester. (Part temperature 10˚C ~ 30˚C)

Normal

8 k" ~ 20 k"

Abnormal

Open or short-circuit

Room temperature
thermistor(RT11)

Indoor coil thermistor
(RT12(MAIN), RT13(SUB))

Vane
motor(MV)

Motor part

Sensor part

Measure the resistance between the terminals with a tester.
(Part temperature 10˚C ~ 30˚C)

BRN – YLW
YLW – GRY

Abnormal

Remain 0V or 5V

Normal

4.5 ~ 5.5V

Measure the voltage power ON.

(When fan revolved one time)

0V➔5V➔0V

(Approx.)

Normal

BRN-other one

Abnormal

Open or short-circuit

Measure the resistance between the terminals with a tester.
(Part temperature 10°C ~ 30°C)

Color of lead wire

Color of lead wire

BLK

RED

WHT

GRY

YLW

BRN

240 " ~ 260 "

Color of lead wire

MAIN
AUX.

FUSE

RED

YLW
BRN

ORN

GRN

ROTOR

Turn OFF the
power supply and
check the connector
CN 211 visually.

No(others)

Disconnect connector from
CN 211 on indoor electronic
control P.C. board.
Measure resistance
between lead wire 1 and 5
and then 3 and 5.

Yes(0 or ∞)

Is resistance
0"(short circuit) or
∞(open circuit)?

Replace the
indoor fan motor.

Replace the
indoor
electronic
control P.C.
board.

CN211

1
3
5

Fan

motor

Indoor electronic
control P.C. board

MSZ-A09YV - MSZ-A12YV -

E1E1

When OPERATION INDICATOR lamp flashes 3-time.
Indoor fan does not operate.

A

Check of indoor fan motor

14

Indoor electronic
control P.C. board

Varistor (NR11)

Indoor electronic
control P.C. board

Fuse (F11)

1
3

CN201

F12

N

2
3

Thermal fuse connector

Terminal

block

Check both “parts side” and “pattern side” of indoor
electronic control P.C. board visually.

Replace the fuse.

Is fuse (F11) blown?

Replace the fan motor.

Is winding resistance
of fan motor 0 "?

Is winding resistance
of vane motor 0 "?

No

Yes

No

Replace the vane motor.

Yes

No

Yes

Is varistor (NR11) burnt?

Replace the varistor.

Yes

Turn OFF the power supply.
Disconnect indoor fan motor connector CN211 and
vane motor connector CN151 from the indoor electronic
control P.C. board and turn ON the power supply.

No

Does the unit operate with the remote controller or
does the OPERATION INDICATOR lamp light up
by pressing the EMERGENCY OPERATION switch?

Yes

No

Turn OFF the
power supply.

Turn OFF the
power supply.

Replace the indoor
electronic control
P.C. board.

Measure the
resistance
between
CN201

1 on

the indoor
electronic control
P.C. board and

N

on the terminal
block with the
tester.

Is resistance approx. 0"?

Replace the fuse (F12).

No

Yes

(∞)

Indoor unit operates by pressing the EMERGENCY OPERATION switch, but does not operate with the remote controller.

CN302

CN125

CN109

12

12

31

543

Remote
controller

Indoor electronic control
P.C. board

Power monitor
receiver P.C.
board

Check of remote controller and receiver P.C. board

B

wCheck if the remote controller is exclusive for this air conditioner.

Switch on the remote controller.

Is LCD display on the the remote
controller visible?

Yes

Remove the batteries, then set them back
and press the RESET button. (Refer to
page 10.) Check if the unit operates with
the remote controller.

Does the unit operate with the
remote controller?

Yes

OK

No
(not clear)

No

Replace the batteries.(Refer to page 10.)

Turn on a radio to AM and press switch on
the remote controller.

Is noise heard from radio?

Yes

Are there any fluorescent lights of
inverter or rapid-start type within
the range of 1m?

No

Measure the voltage between receiver P.C. board connector CN302 No.3(-) and No.5(+) when the remote
controller button is pressed.

Is the voltage approx. 4V DC?

No(5V or 0V DC)

No

Yes

Yes

Replace the remote controller.

● Reinstall the unit away from lights.

● Attach a filter on receiving part.

Replace the indoor electronic control P.C.
board.

The unit doesn’t operate with the remote controller.
Also, the OPERATION INDICATOR lamp doesn’t light up by pressing the EMERGENCY OPERATION switch.

Check of indoor electronic control P.C. board

C

Replace the receiver P.C. board.

15

When OPERATION INDICATOR lamp flashes ON and OFF in every 0.5-second or flashes once.

Is there voltage approx. 280V DC between LD61A
(+) and LD66A (–) on the inverter P.C. board?

Is there approx. 230V AC between outdoor
terminal block 2 and N when EMERGENCY
OPERATION switch is pressed three minutes
after turn OFF the power supply and then turn
ON again?

Is mis-wiring
indicated when
52C turns ON
three minutes
later?

w3 Replace the outdoor
electronic control P.C.

board.

Does the OPERATION INDICATOR lamp flash
quickly when OPERATE/STOP(ON/OFF) button
on the remote controller is pressed?

w2 Mis-wiring may damage indoor electronic

control P.C. board during the operation in
the left. Be sure to confirm the wiring is
correct before the operation starts.

w3 Replace the

indoor electronic
control P.C.
board.

w3 Be sure to release the failure-mode

recall function after checking.

No

w3 Rectify indoor/ outdoor connecting wire.

Yes

A

B

Turn OFF the power supply and confirm that indoor/
outdoor connecting wire is correct.
Short-circuit indoor terminal block N and 3.
During pressing the OPERATION SELECT button and
TOO COOL button on the remote controller, press the
RESET button.
(The above procedure allows OPERATION INDICATOR
lamp to indicate the failure-mode.) w2

Open-circuit indoor terminal block N and 3,
Check if there is amplitude of 5 to 20V DC between
outdoor terminal block N and 3(for confirmation of serial
signal) and if there is 230V AC between 2 and N.

1. Turn OFF the power supply.

2. Disconnect the connector between the compressor and
the transistor module.

3.Turn ON the power supply.

4. Press the EMERGENCY OPERATION switch.

Yes

No

Yes

No

Yes

No

Yes

(light up or OFF)

· Turn OFF inverter-controlled lighting
equipment.

· Turn OFF the power supply and then
turn ON again.

· Press the EMERGENCY
OPERATION switch.

A

B

· Reinstall the
unit away
from light.

· Attach a filter
on receiving
part.

Procedure of release of failure-mode
1 Press the EMERGENCY

OPERATION switch.

2 Turn OFF the power supply and

then turn ON again.

3 Press the RESET button on the

remote controller.

Start

No

• Turn ON the power supply.

•

Press once EMERGENCY OPERATION switch.

Is this mis-wiring, poor contact,
or wire disconnection?

Make them sure.

Yes

After three minutes, mis-wiring is indicated
(0.5-second ON, 0.5-second OFF)
on OPERATION INDICATOR
lamp on indoor unit.w

w Short circuit of JPG and JPS on the indoor
electronic control P.C. board enables
self -check to be displayed in 3 seconds.

•The following indication
applies regardless of shape
of the indicator.

Flashing

Operation Indicator

As for outdoor unit, refer to service manual OB328 or OB319.

Outdoor unit doesn’t operate.

D

How to check mis-wiring

16

When both OPERATION INDICATOR lamps flash 1-time.
Indoor unit and outdoor unit don’t operate.

Check of installation of the horizontal vanes

E

Start

Turn OFF the
power supply.

No

Is the stopper of the horizontal vane
locked to the indoor unit correctly?

Yes

Relock the stopper of the
horizontal vane to the indoor unit.
Refer to page 11.

Turn ON the
power supply.

To check the continuity of safety device,
measure the resistance of connector 1 - 3
connected to CN1R1 on the indoor
electronic control P.C. board.

Is there resistance 0 "?

Yes

Replace the
indoor electronic
control P.C. board.

F

Check of thermal fuse

Turn OFF the
power supply.

No

OK

No(∞)

Is the OPERATION
INDICATOR lamp flashing?

Yes

Turn OFF the
power supply.

Replace the
safety device.

Is resistance ∞ between the connector CN 201 1 on indoor
electronic control P.C. board and the terminal block N?

No

Ok

Yes

Replace the
thermal fuse (F12).

Indoor electronic
control P.C. board

17

CN201

TEST POINT DIAGRAM AND VOLTAGE
MSZ-A09YV - MSZ-A12YV -

E1E1

Indoor electronic control P.C. board

Fuse F11 250V AC 3.15A

Power supply input
230V AC

}

R132

Indoor fan motor
230V AC

}

Safety device of
fan by horizontal
vane CN1R1

Varistor
(NR11)

J12

12V

{

DC

J33

+

–

Power monitor receiver P.C. board

J33

+

–

}

5V DC

J23

Room temperature
thermistor RT11

Indoor coil
thermistor
RT12(MAIN)
RT13(SUB)

Timer short mode
point JPG, JPS

}

(Refer to page 8.)

Emergency
operation switch

Release of Auto restart function
Solder the Jumper wire to the JR07.
(Refer to page 9.)

Indoor coil thermistor [RT12 (MAIN), RT13 (SUB)]
Room temperature thermistor (RT11)

CN302

Resistance (k")

Temperature (:)

18

9

(1) Slide the sleeve and check if there is a locking lever or not. (2) The terminal with this connector is a terminal

with lock mechanism

1Slide the sleeve.
2Pull the terminal while

pushing the locking
lever.

1Hold the sleeve, and
pull out the terminal
slowly.

In case of terminal with lock mechanism, detach the terminal as shown below.
There are two types ( Refer to (1) and (2)) of the terminal with lock mechanism.
The terminal with no lock mechanism can be removed by pulling it out.
Check the shape of the terminal and work.

<"Terminal with lock mechanism" Detaching points>

Connector

Sleeve

Locking lever

DISASSEMBLY INSTRUCTIONS

9-1. MSZ-A09YV - MSZ-A12YV -

E1E1

INDOOR UNIT

OPERATING PROCEDURE

1. Removing the panel

(1) Remove the screw caps of the panel.

Remove the screws.

(2) Pull the panel down to your side slightly and unhook the

catches at the top.

2. Removing the electronic control P.C. board and the
power monitor receiver P.C. board

NOTE : In case of removing only indoor electronic control

P.C. board work (3) is not necessary.
(1) Remove the panel. (Refer to 1.)
(2) Remove the power monitor receiver P.C. board holder from

the bottom of electrical box.

(3) Open the power monitor receiver P.C. board holder and

remove the power monitor receiver P.C. board.

(4) Remove the screw of the electrical cover and the electrical

cover.
(5) Remove the screw of the V.A. clamp and the V.A. clamp.
(6) Remove the screw of the cord clamp and the cord clamp.
(7) Remove the screw of the terminal block.
(8) Remove the screw of the ground wire.
(9) Pull out indoor electronic control P.C. board slightly.
(10)

Disconnect all (except CN109, CN125) the connectors on

the electronic control P.C. board.
(11)

Remove the electronic control P.C. board.

(12)

Disconnect the connector of power monitor receiver P.C.

board (CN109, CN125) on the electronic control P.C.

board.

19

Photo 1

Photo 2

Screw of the
ground wire

Power monitor receiver
P.C. board holder

PHOTOS

Screws of the panel

Terminal block
fixing screw

Indoor electronic
control P.C. board

Cord clamp fixing
screw

Screw of the V.A.
clamp

Screw of the
electrical cover

OPERATING PROCEDURE

PHOTOS

3. Removing the electrical box

(1) Remove the panel. (Refer to 1.)
(2) Remove the electrical cover. (Refer to 2.)
(3) Remove the V.A. clamp. (Refer to 2.)
(4) Remove the cord clamp. (Refer to 2.)
(5) Remove the terminal block. (Refer to 2.)
(6) Remove the screw of ground wire. (Refer to 2.)
(7) Disconnect the connector of the indoor coil thermistor

(CN112), the fan motor connector (CN211 and CN121), the
vane motor connector (CN151) and the connector of the
safety device (CN1R1) on the electronic control P.C. board.

(8) Remove the fan motor lead wire and indoor coil thermistor

from the electrical box.

(9) Remove the lead wire of vane motor and safety device from

the bottom of electrical box.

(10)

Remove the screw fixing the electrical box, remove the

electrical box.

4. Removing the nozzle assembly and the vane motor

(1) Remove the panel. (Refer to 1.)
(2) Remove the electrical box. (Refer to 3.)
(3) Pull out the drain hose from the nozzle assembly, remove

the nozzle assembly.

(4) Remove the screws of the vane motor, disconnect the

vane motor connector.

(5) Remove the vane motor.

Photo 3

Photo 4

Indoor coil thermistor
connector

Fan motor connector

Screws of the vane motor

Vane motor
connector

Screw of the
electrical box

5. Removing the indoor fan motor and the line flow fan

(1) Remove the panel. (Refer to 1.)
(2) Remove the electrical box. (Refer to 3.)
(3) Pull out the drain hose from the nozzle assembly, remove

the nozzle assembly. (Refer to 4.)
(4) Remove the screw of the lead cover and the lead cover.
(5) Remove the lead wire of the fan motor.
(6) Release the hooks of the motor band and open it slightly.
(7) Loosen the hexagon socket set screw of the line flow fan.
(8) Remove the screws fixing the motor bed, remove the fan

motor with motor band and the motor bed.
(9) Remove the screws fixing the left side of the heat

exchanger.
(10)

Lift the left side of the heat exchanger.

(11)

Remove the line flow fan.

Photo 6

Hexagon socket set screw

Drain hose

Photo 5

Screws of the
left side of the
heat exchanger

Photo 7

Screw of
the lead
cover

Hooks of the
motor band

Screws of
the motor
bed

20

PARTS LIST10

MSZ-A09YV - (WH)
MSZ-A12YV - (WH)

E1

E1

10-1. INDOOR UNIT STRUCTURAL PARTS

1 (w)

2

3
4

5

6

10-2. ACCESSORY AND REMOTE

9 (w)

8
7 (See page 23.)

(w) These figures show about MSZ-A12YV.

CONTROLLER

10

11

10-1. INDOOR UNIT STRUCTURAL PARTS

Symbol

No.

E02 749 234

1

E02 751 234

2

E02 838 000

3

E02 749 067

4

E02 838 010

5

E02 408 142
E02 763 100

6

E02 764 100
7
8

E02 749 975

E02 408 970
9

E02 751 970

Part No.

Part name

BOX (WH)
BOX (WH)
PANEL ASSEMBLY (WH)
SCREW CAP
FRONT PANEL (WH)
CATCH
CATECHIN AIR FIL TER
CATECHIN AIR FIL TER
AIR CLEANING FILTER
CORNER BOX (RIGHT)
INSTALLATION PLATE
INSTALLATION PLATE

in Wiring

Diagram

10-2. ACCESSORY AND REMOTE CONTROLLER

E02 838 426

10

E02 527 083

11

REMOTE CONTROLLER
REMOTE CONTROLLER HOLDER

Q'ty/unit

MSZ-A09YV -

(WH)

1

1
2
1
2
2

2
1
1

1
1

E1

MSZ-A12YV -

(WH)

1
1
2
1
2

2
2
1

1

1
1

E1

Including No.3,4,5
2PCS/SET

2PCS/SET

MAC-1300FT

KG04A

Remarks

21

No. Part No.

Part name

Remarks

Symbol

in Wiring

Diagram

Q'ty/unit

1
2
3
4
5
6
7
8

9
10
11

12
13

14
15
16

17
18
19

20
21
22

E02 001 504
E02 661 702
E02 838 235
E02 815 316
E02 838 040
E02 838 041
E02 127 382
E02 829 385
E02 749 385
E02 763 034
E02 815 468
E02 838 452
E02 839 452
E02 749 303
E02 151 308
E02 749 300
E02 751 300
E02 749 333
E02 679 375
E02 665 505
E02 151 505
E02 838 307
E02 749 302
E02 408 509
E02 751 509
E02 408 381

MSZ-A09YV-

E1

MSZ-A12YV-

E1

23

24
25

E02 749 620
E02 839 620
E02 815 666
E02 151 666
E02 151 667

INDOOR HEAT EXCHANGER
INDOOR HEAT EXCHANGER
UNION (GAS)
UNION (GAS)
UNION (LIQUID)

{9.52
{9.52
{6.35

1

1
1

1
1

1

SLEEVE BEARING
DRAIN HOSE
NOZZLE ASSEMBL Y (WH)
SAFETY DEVICE
VANE UPPER
VANE LOWER
FUSE
VARISTOR
VARISTOR
VANE CRANK SET
POWER MONITOR RECEIVER P.C. BOARD
ELECTRONIC CONTROL P.C. BOARD
ELECTRONIC CONTROL P.C. BOARD
VANE MOTOR
ROOM TEMPERATURE THERMISTOR
INDOOR FAN MOTOR
INDOOR FAN MOTOR
MOTOR BAND
TERMINAL BLOCK
FAN MOTOR RUBBER MOUNT
FAN MOTOR RUBBER MOUNT
INDOOR COIL THERMISTOR
LINE FLOW FAN
BEARING MOUNT
BEARING MOUNT
THERMAL FUSE

3.15A

AUTO RESTART
AUTO RESTART

RC4V19­RC4V19-

2PCS/SET
2PCS/SET

93:

F11
NR11
NR12

MV

RT11

MF
MF

TB

RT12, RT13

F12

1
1
1
1
1
1
1
1
1
1
1
1

1
1
1

1
1
2

1
1
1

1

1
1
1
1
1
1
1
1
1
1
1

1
1
1

1
1
1

2
1
1

1
1

(WH)

(WH)

MSZ-A09YV - (WH)
MSZ-A12YV - (WH)

E1

E1

10-3. INDOOR UNIT ELECTRICAL PARTS

10-4. INDOOR UNIT HEAT EXCHANGER

AND FUNCTIONAL PARTS

SLEEVE
BEARING

1

3

4
5
6

21

20

2

FUSE

VARISTOR

7

19

18

17

15

ROOM TEMPERATURE
THERMISTOR

16

14

24

25

13

10

8

9

11

12

(W) This figure shows about MSZ-A12YV.

10-3. INDOOR UNIT ELECTRICAL PARTS AND FUNCTIONAL PARTS

Part number that is circled is not shown in the illustration.

10-4. INDOOR UNIT HEAT EXCHANGER

23 (W)

22

10-5. AIR CLEANING FILTER

MAC-1300FT

Model Part No.

MSZ-A09YV -
MSZ-A12YV -

E1
E1

Air cleaning filter
(White bellows type)

MAC-093SS-E

Model Part No.

MSZ-A09YV -
MSZ-A12YV -

E1
E1

Heat exchanger

● AIR CLEANING FILTER removes fine dust of 0.01 micron from air by means of static electricity.

● Normal life of AIR CLEANING FILTER is 4 months. However, when it becomes dirty, replace it as soon as possible.

● Clogged AIR CLEANING FILTER may reduce the air conditioner capacity or cause frost on the air outlet.

● DO NOT reuse AIR CLEANING FILTER even if it is washed.

● DO NOT remove or attach AIR CLEANING FILTER during unit operation.

OPTIONAL PARTS11

QUICK CLEAN KIT

● You can sweep the surface of heat exchanger if you install the special-made brush to your vacuum cleaner.

23

HEAD OFFICE: MITSUBISHI DENKI BLDG., 2-2-3, MARUNOUCHI, CHIYODA-KU, TOKYO100-8310, JAPAN

CC

Copyright 2004 MITSUBISHI ELECTRIC ENGINEERING CO.,LTD
Distributed in Jan. 2004. No. OB327 6
Made in Japan

New publication, effective Jan. 2004
Specifications subject to change without notice.