AOC 212Va User manual

22" LCD Color Monitor AOC 212Va
1
Service
Service
Service
Horizontal Frequency
31.5 kHz - 80 KHz
TABLEOFCONTENTS
Description Page Description Page
SAFETY NOTICE
ANY PERSON ATTEMPTING TO SERVICE THIS CHASSIS MUST FAMILIARIZE HIMSELF WITH THE CHASSIS
AND BE AWARE OF THE NECESSARY SAFETY PRECAUTIONS TO BE USED WHEN SERVICING
ELECTRONIC EQUIPMENT CONTAINING HIGH VOLTAGES.
Table Of Contents.......……...................................…........1
Revision List.…...................................................……......2
Important Safety Notice.……..............................……......3
1.Monitor Specification..................................………........4
2.LCD Monitor Description………….………………….......6
3.Operation Instruction…………….................……...........7
3.1.General Instructions....................................…...........7
3.2.Control Button…………….…..............……...............7
3.3.OSD Menu…………….…...........................…............8
4.Input/Output Specification............……………............11
4.1.Input Signal Connector............……………...............11
4.2.Factory Preset Display Modes.................................12
4.3.Panel Specification.....………...…………..................13
5.Block Diagram…..…...................………..…................15
5.1.Software Flow Chart……………..…………....….......15
5.2.Electrical Block Diagram…………….………..….......17
6.Schematic……………......................................19
6.1 Main Board…….....................................................19
6.2 Power Board....……..............................................23
6.3 Audio Board.............……....................................25
7.PCB Layout..………….......................................26
7.1.Main Board………..……........................................26
7.2.Power Board....……….........................................29
7.3 Audio Board...............……....................................32
7.4.Key Board……………............................................32
8.Maintainability……….......................................33
8.1.Equipments and Tools Requirement......................33
8.2.Trouble Shooting………….....................................34
9.White-Balance, Luminance adjustment…….............40
10.Monitor Exploded View……….………….…............42
11.BOM List…………..…………………………............43
CAUTION: USE A SEPARATE ISOLATION TRANSFOMER FOR THIS UNIT WHEN SERVICING

22" LCD Color Monitor AOC 212Va
2
Revision List
Version Release Date Revision History TPV Model Name
A00 May.10, 2007 Initial release TC6MMADQWJAO8

22" LCD Color Monitor AOC 212Va
3
Important Safety Notice
Proper service and repair is important to the safe, reliable operation of all AOC Company Equipment. The service
procedures recommended by AOC and described in this service manual are effective methods of performing service
operations. Some of these service operations require the use of tools specially designed for the purpose. The special
tools should be used when and as recommended.
It is important to note that this manual contains various CAUTIONS and NOTICES which should be carefully read in
order to minimize the risk of personal injury to service personnel. The possibility exists that improper service
methods may damage the equipment. It is also important to understand that these CAUTIONS and NOTICES ARE
NOT EXHAUSTIVE. AOC could not possibly know, evaluate and advise the service trade of all conceivable ways in
which service might be done or of the possible hazardous consequences of each way. Consequently, AOC has not
undertaken any such broad evaluation. Accordingly, a servicer who uses a service procedure or tool which is not
recommended by AOC must first satisfy himself thoroughly that neither his safety nor the safe operation of the
equipment will be jeopardized by the service method selected.
Hereafter throughout this manual, AOC Company will be referred to as AOC.
WARNING
Use of substitute replacement parts, which do not have the same, specified safety characteristics may create shock,
fire, or other hazards.
Under no circumstances should the original design be modified or altered without written permission from AOC. AOC
assumes no liability, express or implied, arising out of any unauthorized modification of design.
Servicer assumes all liability.
FOR PRODUCTS CONTAINING LASER:
DANGER-Invisible laser radiation when open AVOID DIRECT EXPOSURE TO BEAM.
CAUTION-Use of controls or adjustments or performance of procedures other than those specified herein may result
in hazardous radiation exposure.
CAUTION -The use of optical instruments with this product will increase eye hazard.
TO ENSURE THE CONTINUED RELIABILITY OF THIS PRODUCT, USE ONLY ORIGINAL MANUFACTURER'S
REPLACEMENT PARTS, WHICH ARE LISTED WITH THEIR PART NUMBERS IN THE PARTS LIST SECTION OF
THIS SERVICE MANUAL.
Take care during handling the LCD module with backlight unit
-Must mount the module using mounting holes arranged in four corners.
-Do not press on the panel, edge of the frame strongly or electric shock as this will result in damage to the screen.
-Do not scratch or press on the panel with any sharp objects, such as pencil or pen as this may result in damage to
the panel.
-Protect the module from the ESD as it may damage the electronic circuit (C-MOS).
-Make certain that treatment person’s body is grounded through wristband.
-Do not leave the module in high temperature and in areas of high humidity for a long time.
-Avoid contact with water as it may a short circuit within the module.
-If the surface of panel becomes dirty, please wipe it off with a soft material. (Cleaning with a dirty or rough cloth may
damage the panel.)

22" LCD Color Monitor AOC 212Va
4
1. Monitor Specifications
Model number 212Va
Driving system TFT Color LCD
Size 559mm ( 22" 16:10)
Pixel pitch 0.282mm(H) x 0.282mm(V)
Video R, G, B Analog lnterface
Separate Sync. H/V TTL
Display Color 16.7 million Colors
LCD Panel
Dot Clock 149MHz
Horizontal scan range 31.5 kHz - 80 KHz
Horizontal scan Size(Maximum) 473.76mm
Vertical scan range 55 Hz - 75 Hz
Vertical scan Size(Maximum) 296.1mm
Optimal preset resolution 1680 x 1050 (60 Hz)
Highest preset resolution 1680 x 1050 (60 Hz)
Plug & Play VESA DDC2B
Input Connector D-Sub 15pin ,DVI 24 pin
Input Video Signal Analog / DVI-D
Power Source 100~240VAC, 47~63Hz
Active < 49W
Resolution
Power Consumption
Standby < 2W
Connector Type 15-pin D-Sub,24 pin DVI
Signal Cable Type Detachable
Dimensions & Weight:
Height (with base) 428.32 mm
Width 505.20 mm
Depth 210.82 mm
Weight (monitor only) 6 kg
Physical
Characteristics
Weight (with packaging) 8 kg
Temperature:
Operating 0° to 40°
Non-Operating -20°to 60°
Environmental
Humidity:

22" LCD Color Monitor AOC 212Va
5
Operating 10% to 85% (non-condensing)
Non-Operating 5% to 80% (non-condensing)
Altitude:
Operating 0~ 3000m (0~ 10000 ft )
Non-Operating 0~ 5000m (0~ 15000 ft )
Regulations CE/TCO03

22" LCD Color Monitor AOC 212Va
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2. LCD Monitor Description
The LCD monitor will contain a main board, a power board, key board and audio board which house the flat panel
control logic, brightness control logic and DDC.
The power board will provide AC to DC Inverter voltage to drive the backlight of panel and the main board chips each
voltage.
Monitor Block Diagram
AC-IN
100V-240V
Power board
(
Include: ada
p
ter, inverter
)
Flat Panel and
CCFL backlight
Main Board RS232 Connector
For white balance
adjustment in factory
mode
CCFL Drive.
Video signal, DDC
Key Board
HOST Computer
Audio Board

22" LCD Color Monitor AOC 212Va
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3. Operating Instructions
3.1 General Instructions
Press the power button to turn the monitor on or off. The other control buttons are located at the front of the panel
of the monitor.
By changing these settings, the picture can be adjusted to your personal preferences.
-The power cord should be connected.
-Press the power button to turn on the monitor, the power indicator will light up.
3.2 Control Buttons
3.2.1 Key Control
3.2.2 Key Function
1. Auto Config 4. Menu
2. - / Volume down 5. Source
3. + / Volume up 6. Power Button & Indicator
3.2.3 Attaching the Cables

22" LCD Color Monitor AOC 212Va
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Turn off your computer before performing the procedure below.
1. Connect the power cable to the AC port on the back of the monitor.
2. Connect one end of the 15-pin D-Sub cable to the back of the monitor and connect the other end to the
computer's D-Sub port.
3. (Optional - Requires a video card with DVI port) - Connect one end of the 24-pin DVI cable to the back of the
monitor and connect the other end to the computer's DVI port
4. Turn on your monitor and computer.
OSD Settings
•Press the MENU-button to activate the OSD window.
•Press+ or - to navigate through the functions. Once the desired function is highlighted, press the MENU-button to
activate it. If the function selected has a sub-menu, press or again to navigate through the sub-menu functions.
Once the desired function is highlighted, press MENU-button to activate it.
•Press+ or - to change the settings of the selected function. To exit and save, select the exit function. If you want
to adjust any other function, repeat steps 2-3.
•OSD Lock Function: To lock the OSD, press and hold the MENU button while the monitor is off and then press
power button to turn the monitor on. To un-lock the OSD - press and hold the MENU button while the monitor is
off and then press power button to turn the monitor on.
•Press Auto key continually for 7 sec. to turn on or off DDC-CI.
3.3 OSD Menu
1. Power
2. Audio
3. DVI
4. Analog

22" LCD Color Monitor AOC 212Va
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Function Control Illustration
Luminance Adjust Range Description
Brightness 0-100 Backlight Adjustment
Contrast 0-100 Contrast from Digital-register.
Standard Standard Mode
Text Text Mode
Internet Internet Mode
Game Game Mode
Movie Movie Mode
Eco mode
Sports Sports Mode
Gamma1 Adjust to Gamma1
Gamma2 Adjust to Gamma 2
Gamma
Gamma3 Adjust to Gamma 3
Off Disable dynamic contrast ratio
DCR
On Enable dynamic contrast ratio
Image Setup
Clock 0-100 Adjust picture Clock to reduce Vertical-Line
noise.
Focus 0-100 Adjust Picture Phase to reduce Horizontal-Line
noise
H.Position 0-100 Adjust the vertical position of the picture.
V.Position 0-100 Adjust the horizontal position of the picture.
Color Temp.
Warm Recall Warm Color Temperature from EEPROM.
Normal
Recall Normal Color Temperature from
EEPROM.
Cool Recall Cool Color Temperature from EEPROM.
sRGB Recall SRGB Color Temperature from EEPROM.
User-B Blue Gain from Digital-register
User-G Green Gain Digital-register.
User-R Red Gain from Digital-register
User-Y Yellow Gain from Digital-register
User-C Cyan Gain from Digital-register
User
User-M Magenta Gain from Digital-register

22" LCD Color Monitor AOC 212Va
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Color Boost
Full Enhance on or off Disable or Enable Full Enhance Mode
Nature Skin on or off Disable or Enable Nature Skin Mode
Green Field on or off Disable or Enable Green Field Mode
Sky-blue on or off Disable or Enable Sky-blue Mode
AutoDetect on or off Disable or Enable AutoDetect Mode
Demo on or off Disable or Enable Demo
Picture Boost
Frame Size 0-100 Adjust Frame Size
Brightness 0-100 Adjust Frame Brightness
Contrast 0-100 Adjust Frame Contrast
Hue 0-100 Adjust Frame Hue
Saturation 0-100 Adjust Frame Saturation
H. position Adjust Frame horizontal Position
Position
V.position Adjust Frame vertical Position
Bright Frame on or off Disable or Enable Bright Frame
OSD Setup
H.Position 0-100 Adjust the vertical position of OSD
V.Position 0-100 Adjust the horizontal position of OSD
Timeout 0-100 Adjust the OSD Timeout
Language Select the OSD language
Extra
Digital Select Digital Signal Source as Input
Input Select
Analog Select Analog Signal Source as Input
Auto Config yes or no Auto adjust the picture to default
Reset yes or no Reset the menu to default
DDC-CI Turn ON/OFF DDC-CI Support
Information
Show the information of the main image and
sub-image source
LED Indicators
Status LED Color
Full Power Mode Green
Active-off Mode Orange

22" LCD Color Monitor AOC 212Va
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4. Input/Output Specification
4.1 Input Signal Connector
Pin No. Description Pin No. Description
1. Video-Red 9. +5V
2. Video-Green 10. Detect Cable
3. Video-Blue 11. NC
4. NC 12. DDC-Serial Data
5. GND 13. H-Sync
6. GND-R 14. V-Sync
7. GND-G 15. DDC-Serial clock
8. GND-B
VGA connector layout
Pin No. Signal Name Pin No. Signal Name Pin No. Signal Name
1 TMDS Data 2- 9 TMDS Data 1- 17 TMDS Data 0-
2 TMDS Data 2+ 10 TMDS Data 1+ 18 TMDS Data 0+
3 TMDS Data 2/4 Shield 11 TMDS Data 1/3 Shield 19 TMDS Data 0/5 Shield
4 TMDS Data 4- 12 TMDS Data 3- 20 TMDS Data 5-
5 TMDS Data 4+ 13 TMDS Data 3+ 21 TMDS Data 5+
6 DDC Clock 14 +5V Power 22 TMDS Clock Shield
7 DDC Data 15 Ground(for+5V) 23 TMDS Clock +
8 N.C. 16 Hot Plug Detect 24 TMDS Clock -
DVI connector layout

22" LCD Color Monitor AOC 212Va
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4.2 Factory Preset Display Modes
Stand Resolution
Horizontal
Frequency(KHz)
Vertical
Frequency(Hz)
Dos-mode 720 x 400 31.47 70.0
VGA 640 x 480 31.47 60.0
VGA 640 x 480 37.50 75.0
SVGA 800 x 600 37.879 60.0
SVGA 800 x 600 46.875 75.0
XGA 1024 x 768 48.363 60.0
XGA 1024 x 768 56.476 70.0
XGA 1024 x 768 60.02 75.0
XGA 1024 x 768 48.780 60.0
XGA 1024 x 768 60.241 75.0
SXGA 1280 x 1024 64.00 60.0
SXGA 1280 x 1024 80.00 75.0
WSXGA 1680 x 1050 65.29 60.0
UXGA 1600 x 1200 37.50 60.0

22" LCD Color Monitor AOC 212Va
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4.3 Panel Specification
4.3.1 General Features
The M220Z1-L01 model is a 22 inch wide TFT-LCD module with a 4-CCFL Backlight Unit and a 30-pin
2ch-LVDS interface. This module supports 1680 x 1050 WSXGA+ (16:10 wide screen) mode and displays
up to 16.7 millions colors. The inverter module for the Backlight Unit is not built in.
4.3.2 Features
4.3.3 Display Characteristics

22" LCD Color Monitor AOC 212Va
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4.3.4 Optical Characteristics
4.3.5 Electrical Characteristics
(1) TFT- LCD
(2) Backlight

22" LCD Color Monitor AOC 212Va
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5. Block Diagram
5.1 Software Flow Chat
1
2
N
Y
5
Y
N
10
Y
N
12
Y
N
7
Y
N
6
4
3
8
9
14
11
13
Y
N
15
Y
N16
17
19
Y
N
18

22" LCD Color Monitor AOC 212Va
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1) MCU initialize.
2) Is the EPROM blank?
3) Program the EPROM by default values.
4) Get the PWM value of brightness from EPROM.
5) Is the power key pressed?
6) Clear all global flags.
7) Are the AUTO and SELECT keys pressed?
8) Enter factory mode.
9) Save the power key status into EPROM.
Turn on the LED and set it to green color.
Scalar initializes.
10) In standby mode?
11) Update the lifetime of back light.
12) Check the analog port, are there any signals coming?
13) Does the scalar send out an interrupt request?
14) Wake up the scalar.
15) Are there any signals coming from analog port?
16) Display "No connection Check Signal Cable" message. And go into standby mode after the message
disappear.
17) Program the scalar to be able to show the coming mode.
18) Process the OSD display.
19) Read the keyboard. Is the power key pressed?

22" LCD Color Monitor AOC 212Va
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5.2 Electrical Block Diagram
5.2.1 Main Board
EEPROM
M24C02
(U404)
EEPROM
24LC16B/SNG
(U403)
Panel Interface
(CN101)
SDA
SCL
Crystal
14.318MHZ
(X401)
Flash Memory
PM25LV010-25 SCE
(U402)
Scalar TSUMU58WHJ-LF
(Include MCU, ADC, OSD)
(U401)
H sync
V sync
RGB
DDCA_SDA,
DDC
A_
SCL
D-Sub
Connector
(CN405)
Key Control
Interface
(CN403)
EEPROM
M24C02
(U405)
DDCD_SDA,
DDCD_SCL
DVI
Connector
(CN406)
Digital Video
Signal

22" LCD Color Monitor AOC 212Va
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5.2.2 Inverter/Power Board
CN902
DIM
DIM
EMI filter
Start Circuit: R904, R932, R933
PWM
Control IC
Transformer
AC input
5V
ON/OFF
Control
PWM
Control IC
Feedback
Circuit
Output
Circuit Transformer MOSFET
Over
Voltage
Lamp
ON/OFF
12V
Bridge
Rectifier
and Filter
Feedback
Circuit
Rectifier
diodes

22"LCDColorMonitor AOC212Va
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6. Schematic
6.1 Main Board
715G2186-1
+
C717
100uF/25V
BL_ADJ
D704
SR24
Q703
PMBS3904
C704
NC
R713 NC
VCC3.3 4
+3V3
+3V3
C701
0.1uF
U702
AIC1084-33PM
3
1
2
VIN
ADJ
VOUT
Q704
AO3401
R703
2K 1/10W
R722
NC
TO-263
+3V3
+5V
R716
NC
D701
GS1D
U701
NC
3 2
1
VI VO
GND
CN701
CONN
2
4
6
8
10
12
1
3
5
7
9
11
R701
1K 1/10W
+3V3
VCTRL 4
+
C702
4.7uF/50V VCC1.8 4
+12V
Q706
NC
+5V
R706 NC
R725 4.7K 1/10W
R727
10K 1/10W
GND
GND
GND
GND
+5V
GND
R702
51 1/10W
R710 NC
R712
4.7K 1/10W
Q705
PMBS3906
GND
715G2186-1
B
POWER
Custom
25Thursday , October 12, 2006
Tit le
Size Document Number Rev
Date: Sheet of
+12V
R721
0 1/10W
+
C707
NC
VCC3.3
+5V
R723
10K 1/10W
+12V
+
C710
100uF/25V
R704
100 1/10W
Adj_BACKLIGHT 4
C714
0.1uF
+5V
SOT-223
R707
4.7K 1/10W
R709 15K 1/10W
+5V
L702
120 OHM
1 2
C711
0.1uF
VCC3.3
C715
0.022uF
C718
NC
Reservation schematic-
for blacklight off have
panel on solution.
R714
10K 1/10W
VCC3.3 4
+5V 3,4
Q701
PMBS3904
R705
4.7K 1/10W
R717
10K 1/10W
VLCD
+5V
on_Panel4
VCC1.8
C708
NC
Q702
PZT2907A
R715
NC
C709
0.1uF
C706
0.1uF
R708
10K 1/10W
+
C703
NC
VLCD 5
on_BACKLIGHT 4
C719
0.1uF
+5V
+
C722
22uF/50V
+
C712
100uF/25V
+5V3,4
R711
10K 1/10W
C713
0.1uF
D702
LL4148

22"LCDColorMonitor AOC212Va
20
D424
BAV99
3
1 2
R457 10K 1/10W
DAT2-
GIN 4
PC5V
U405
M24C02-WMN6TP
1
2
3
45
6
7
8A0
A1
A2
GNDSDA
SCL
WP
VCC
GNDB 4
R468 10 1/10W
D413
BAV70
3
1 2
G+ 4
D406
ZMM5V6
1 2
D425
RLZ36B
1 2
R444
10K 1/10W
C447
0.1uF
GNDR 4
C432 0.047uF
GREEN-
FB409 430 OHM
C445
0.1uF
Q406
NC R461
10K 1/10W
D421
BAV99
3
1 2
B- 4
D415
ZMM5V6
1 2
R466 10 1/10W
C450
0.1uF
R448
2.2K 1/10W
R436 56 1/10W
R434 56 1/10W
D417
BAV99
3
1 2
+5V
R437 470 1/10W PC5V
SDA_DVI
DAT0+
R469 10 1/10W
DVI5V
R472
NC
R453 100 1/10W
RED+ FB410 0 1/10W
C441
0.047uF
+5V
CLK- 4
DDC_WP 4
D418
BAV99
3
1 2
D412
ZMM5V6
1 2
VSYNC 4
C442
22pF
C438 0.047uF
+5V
RIN 4
HSYNC 4
ESD_5V
B+ 4
SCL_VGA
D414
ZMM5V6
1 2
R471
10K 1/10W
R459
10K 1/10W
C449
0.1uF
DET_DVI 4
DDCA_SCL4
+5V
FB411 0 1/10W
BLUE-
DCLK-
C451
0.1uF
D405
BAV99
3
1 2
R455 100 1/10W
C453
0.1uF
CN405
DB15
1
6
2
7
3
8
4
9
5
11
12
13
14
15
10
1716
D404
BAV99
3
1 2
R470
1K 1/10W
R456 100 1/10W
VSI
R442 100 1/10W
DAT2+
C448
0.1uF
C436 0.047uF
D411
ZMM5V6
1 2
R452
10K 1/10W
+5V
C444
0.1uF
R458 100 1/10W
D419
BAV99
3
1 2
HDCP_RST 4
PC5V
DDCA_SDA4
DAT1- G- 4
R450
10K 1/10W
RED-
C452
0.1uF
DDCD_SDA4
SCL_DVI
R451
10K 1/10W
CN406
JACK
1
2
3
4
5
6
7
8
25
28
9
10
11
12
13
14
15
16
26
29
17
18
19
20
21
22
23
24
27
32 31
DAT2-
DAT2+
2/4shield
DAT4-
DAT4+
DDC SCL
DDC SDA
VSYNC
R
HSYNC
DAT1-
DAT1+
1/3shield
DAT3-
DAT3+
+5V
SYNC GND
HPD
G
RGB GND
DAT0-
DAT0+
0/5shield
DAT5-
DAT5+
clk shield
clk+
clk-
B
GND GND
R445 100 1/10W
R+ 4
BLUE+
DAT1+
HPD
R446 1K 1/10W
D420
BAV99
3
1 2
BIN 4
C440
0.047uF
DVI5V
R443 100 1/10W
R464 10 1/10W
C434 0.047uF
D403
BAV99
3
1 2
SOG 4
D408
ZMM5V6
1 2
VGA_CON
D410
ZMM5V6
1 2
R454 100 1/10W
U404
M24C02-WMN6TP
1
2
3
45
6
7
8A0
A1
A2
GNDSDA
SCL
WP
VCC
DDCD_SCL4
R401
NC
715G2186-1
DVI5V
C446
0.1uF
R449
2.2K 1/10W
R435 56 1/10W
R439
75 1/10W
D409
ZMM5V6
1 2
D422
BAV99
3
1 2
CLK+ 4
B
INPUT
B
35Thursday , October 12, 2006
Ti t le
Size Document Number Rev
Date: Sheet of
GNDG 4
HSI
R462 10 1/10W
D416
ZMM5V6
1 2
C439
0.047uF
SDA_VGA
R438
75 1/10W
DET_VGA 4
DCLK+
R440
75 1/10W
D423
BAV99
3
1 2
R467 10 1/10W
R- 4
DAT0-
FB412 0 1/10W
C443
220pF
C435 0.001uF
R465 10 1/10W
R447 1K 1/10W
+5V 2,4
R441 100 1/10W
R473
NC
DDC_WP 4
GREEN+
C437 0.047uF
C454
0.1uF
ESD_5V
D426
ZMM5V6
1 2
R463 10 1/10W
R460
10K 1/10W
C433 0.047uF
D407
BAV70
3
1 2