LG 42PJ350 Schematic

Training Manual

42PJ350 Plasma Display

Advanced Single Scan Troubleshooting

42" Class HD 720p Plasma TV

(41.6" diagonally)

Published August 12th, 2010

Updated February 3rd, 2011

OUTLINE

Overview of Topics to be Discussed

Preliminary:

Contact Information, Preliminary Matters, Specifications,

Plasma Overview, General Troubleshooting Steps,

Disassembly Instructions, Voltage and Signal Distribution

No Main Power Switch (Vacation Switch).

Troubleshooting:

Circuit Board Operation, Troubleshooting and Alignment of :

•Switch Mode Power Supply No VS On command input to SMPS

•Y-SUS Board Delivers Logic Signals and FG5V to Y-Drive board.

•Y-Drive Board

•Z-SUS Output Board (Also uses one Z-SUB board for bottom panel connector)

•Control Board

•X Drive Boards (2)

•Main Board

•Interconnect Diagram: 11X17 Foldout Section used as a quick reference sheet.

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Overview of Topics to be Discussed

42PJ350 Plasma Display

The first section will cover Contact Information and Important Safety Precautions for the Customers Safety as well as the Technician and the Equipment.

Basic Troubleshooting Techniques which can save time and money sometimes can be overlooked. These techniques will also be presented.

The next section will get the Technician familiar with the Disassembly, Identification and Layout of the Plasma Display Panel.

At the end of this Section the Technician should be able to Identify the Circuit Boards and have the ability and knowledge necessary to safely remove and replace any Circuit Board or Assembly.

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LG Contact Information

Customer Service (and Part Sales)		[phone]
Technical Support (and Part Sales)		[phone]
USA Website (GSFS)	http://gsfs-america.lge.com
Customer Service Website	http://www.us.lgservice.com
Knowledgebase Website	http://lgtechassist.com		New: 2010 Models Software
			Downloads Technical Assistance
LG Web Training	https://lge.webex.com		Presentations with Audio/Video
			and Screen Marks
LG CS Academy	http://ln.lge.com/ilearn
			http://136.166.4.200

LCD-DV: 32LG40, 32LH30, 37LH55, 42LG60, 42LG70, 42LH20, 42LH40, 42LH50, 42LH90, 42SL80,

47LG90, 47LH85, 42LE5500, 47LE8500

PLASMA: 42PG20, 42PJ350, 42PQ20, 42PQ30, 50PG20, 50PJ350, 50PK250, 50PK750, 50PS80, 50PS60, 60PK750, 60PS11, 60PS60, 60PS80

Also available on the Plasma Page:	New Training Materials on
PDP Panel Alignment Handbook, Schematics with Bookmarks
Plasma Control Board ROM Update (Jig required)	the Learning Academy site

Published August 2010 by LG Technical Support and Training

LG Electronics Alabama, Inc.

201 James Record Road, Huntsville, AL, 35813.

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Preliminary Matters (The Fine Print)

IMPORTANT SAFETY NOTICE

The information in this training manual is intended for use by persons possessing an adequate background in electrical equipment, electronic devices, and mechanical systems. In any attempt to repair a major Product, personal injury and property damage can result. The manufacturer or

seller maintains no liability for the interpretation of this information, nor can it assume any liability in conjunction with its use. When servicing this product, under no circumstances should the original design be modified or altered without permission from LG Electronics. Unauthorized modifications will not only void the warranty, but may lead to property damage or user injury.

If wires, screws, clips, straps, nuts, or washers used to complete a ground path are removed for service, they must be returned to their original positions and properly fastened.

CAUTION

To avoid personal injury, disconnect the power before servicing this product. If electrical power is required for diagnosis or test purposes, disconnect the power immediately after performing the

necessary checks. Also be aware that many household products present a weight hazard. At least two people should be involved in the installation or servicing of such devices. Failure to consider the weight of an product could result in physical injury.

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ESD Notice

(Electrostatic Static Discharge)

Today’s sophisticated electronics are electrostatic discharge (ESD) sensitive. ESD can weaken or damage the electronics in a manner that renders them inoperative or reduces the time until their next failure. Connect an ESD wrist strap to a ground connection point or unpainted metal in the product. Alternatively, you can touch your finger repeatedly to a ground connection point or unpainted metal in the product. Before removing a replacement part from its package, touch the anti-static bag to a ground connection point or unpainted metal in the product. Handle the electronic control assembly by its edges only. When repackaging a failed electronic control assembly in an anti-static bag, observe these same precautions.

Regulatory Information

This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference when the equipment is operated in a residential installation. This equipment generates, uses, and can radiate radio frequency energy, and, if not installed and used in accordance with the instruction manual, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is

encouraged to try to correct the interference by one or more of the following measures: Reorient or relocate the receiving antenna; Increase the separation between the equipment and the receiver; Connect the equipment to an outlet on a different circuit than that to which the receiver is connected; or consult the dealer or an experienced radio/TV technician for help.

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Safety and Handling, Checking Points

Safety & Handling Regulations

1.Approximately 10 minute pre-run time is required before any adjustments are performed.

2.Refer to the Voltage Sticker inside the Panel when making adjustments on the Power Supply, Y-SUS and Z-SUS Boards.

3.Always adjust to the specified voltage level (+/- ½ volt) unless otherwise specified.

4.Be cautious of electric shock from the PDP module since the PDP module uses high voltage, check that the Power Supply and Drive Circuits are completely discharged because of residual current stored before Circuit Board removal.

4.C-MOS circuits are used extensively for processing the Drive Signals and should be protected from static electricity.

5.The PDP Module must be carried by two people. Always carry vertical NOT horizontal.

6.The Plasma television should be transported vertically NOT horizontally.

7.Exercise care when making voltage and waveform checks to prevent costly short circuits from damaging the unit.

8.Be cautious of lost screws and other metal objects to prevent a possible short in the circuitry.

9.New Panels and Frames are much thinner than previous models. Be Careful with flexing these panels. Be careful with lifting Panels from a horizontal position. Damage to the Frame mounts or panel can occur.

10.New Plasma models have much thinner cabinet assemblies and mounts. Be extremely careful when moving the set around as damage can occur.

Checking Points to be Considered

1.Check the appearance of the Replacement Panel and Circuit Boards for both physical damage and part number accuracy.

2.Check the model label. Verify model names and board model matches.

3.Check details of defective condition and history. Example: Y-SUS or Y-Drive Board Failure, Mal-discharge on screen, etc.

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Basic Troubleshooting Steps

Define, Localize, Isolate and Correct

•Define Look at the symptom carefully and determine what circuits could be causing the failure. Use your senses Sight, Smell, Touch and Hearing. Look for burned parts and check for possible overheated components. Capacitors will sometimes leak dielectric material and give off a distinct odor. Frequency of power supplies will change with the load, or listen for relay closing etc. Observation of the front Power LEDs may give some clues.

•Localize After carefully checking the symptom and determining the circuits to be checked and after giving a thorough examination using your senses the first check should always be the DC Supply Voltages to those circuits under test. Always confirm the supplies are not only the proper level but be sure they are noise free. If the supplies are missing check the resistance for possible short circuits.

•Isolate To further isolate the failure, check for the proper waveforms with the Oscilloscope to make a final determination of the failure. Look for correct Amplitude Phasing and Timing of the signals also check for the proper Duty Cycle of the signals. Sometimes “glitches” or “road bumps” will be an indication of an imminent failure.

•Correct The final step is to correct the problem. Be careful of ESD and make sure to check the DC Supplies for proper levels. Make all necessary adjustments and lastly always perform a Safety AC Leakage Test before returning the product back to the Customer.

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42PJ350 PRODUCT INFORMATION SECTION

This section of the manual will discuss the specifications of the 42PJ350 Advanced Single Scan Plasma Display Television.

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42PJ350 Specifications

1080P PLASMA HDTV

42" Class (41.6" diagonal)

•600Hz Sub Field Driving

•High Definition Resolution

•3M:1 Dynamic Contrast Ratio

•TruSlim Frame

•Picture Wizard II (Easy Picture Calibration)

•Smart Energy Saving

•Intelligent Sensor

•Dual XD™ Engine

•AV Mode (Cinema, Sports, Game)

•Clear Voice II

•ISFccc® Ready

•24P Real Cinema

•USB 2.0 (JPEG, MP3)

•3 HDMI™ 1.3 Inputs

•SIMPLINK™ Connectivity

•Dolby® Digital 5.1 Decoder

•Infinite Sound

For Full Specifications

See the Specification Sheet

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42PJ350 Logo Familiarization Page 1 of 3

600Hz Sub Field Firing:

Capture every moment. Tired of streaky action or unclear plays during the game? See sports, fast action and video games like never before. The 600Hz refresh rate virtually eliminates motion blur.

3.000,000 : 1 Contrast Ratio

Stunning detail. No more worrying about dark scenes or dull colors.

The Mega Contrast ratio of 3,000,000:1 delivers more stunning colors and deeper blacks than you can imagine.

TruSlim Design:

At less than 1" thick the new TruSlim Frame trims away distraction without compromising screen size.

USB 2.0:

View videos and photos and listen to music on your TV through USB 2.0.

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42PJ350 Logo Familiarization Page 2 of 3

HD RESOLUTION 720P HD Resolution Pixels: 1365 (H) × 768 (V)

See and experience more. Pictures are sharper.

Colors are more vibrant. Entertainment is more real.

Everything looks better on an HDTV.

HDMI (1.3 Deep Color) Digital multi-connectivity

HDMI (1.3 Deep color) provides a wider bandwidth (340MHz, 10.2Gbps) than that of HDMI 1.2, delivering a broader range of colors, and also drastically improves the data-transmission speed.

Invisible Speaker

Personally tuned by Mr. Mark Levinson for LG

TAKE IT TO THE EDGE newly introduces ‘Invisible Speaker’ system,

guaranteeing first class audio quality personally tuned by Mr. Mark Levinson, world renowned as an audio authority. It provides Full Sweet Spot and realistic sound equal to that of theaters with its Invisible Speaker.

Dual XD Engine

Realizing optimal quality for all images

One XD Engine optimizes the images from RF signals as another XD Engine optimizes them from External inputs. Dual XD Engine presents images with optimal quality two times higher than those of previous models.

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42PJ350 Logo Familiarization Page 3 of 3

AV Mode "One click" Cinema, Sports, Game mode.

AV Mode is three preset picture and audio settings. It allows the viewer to quickly switch between common settings. It includes Cinema, Sports, and Game Modes.

Clear Voice Clearer dialogue sound

Automatically enhances and amplifies the sound of the human voice frequency range to provide high-quality dialogue when background noise swells.

Save Energy, Save Money

It reduces the plasma display’s power consumption.

The default factory setting complies with the Energy Star requirements

and is adjusted to the comfortable level to be viewed at home. (Turns on Intelligent Sensor).

Save Energy, Save Money

Home electronic products use energy when they're off to power features like clock displays and remote controls. Those that have earned the ENERGY STAR use as much as 60% less energy to perform these functions, while providing the same performance at the same price as less-efficient models. Less energy means you pay less on your energy bill. Draws less than 1 Watt in stand by.

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600Hz Sub Field Driving

(600 Hz Sub Field Driving)

•600 Hz Sub Field Driving is achieved by using 10 sub-fields per frame process (vs. Comp. 8 sub-field/frame)

•No smeared images during fast motion scenes

Original Image	10 Sub Fields Per Frame

Sub Field firing occurs using wall charge and polarity differences between Y-SUS and Z-SUS signals.

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42PJ350 Remote Control

BOTTOM PORTION

p/n AKB72914201 TOP PORTION

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42PJ350 Rear and Side Input Jacks

AC In	USB for Music, Photos
	and Software
	Upgrades
	SIDE
	INPUTS

REAR

INPUTS

USB

HDMI 3

Composite

Video/Audio

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Accessing the Service Menu

To access the Service Menu.

1)You must have either Service Remote. p/n 105-201M or p/n MKJ39170828

2)Press “In-Start”

3)A Password screen appears.

4)Enter the Password.

Note: A Password is required to enter the

Service Menu. Enter; 0000

Note: If 0000 does not work use 0413.

105-201M		MKJ39170828
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Generic Plasma USB Automatic Software Download Instructions

1) Download the Software File.

2)Copy new software (xxx.bin) into the root of the Jump Drive. Make sure you have the correct software file.

3)With TV turned on, insert USB flash drive.

4)You can see the message

“TV Software Upgrade” (See figure on right)

5)Cursor left and highlight "START" Button and push “Enter” button using the remote control.

6)You can see the download progress Bar.

7)Do not unplug until unit has automatically restarted.

8)When download is completed, you will see “COMPLETE”.

9)Your TV will be restarted automatically.

Currently Installed Version

Software Version found on the USB Flash Drive

File found on the USB

Flash Drive

Highlight Start Press Select

* CAUTION:

Do not remove AC power or the USB Flash Drive. Do not turn off Power, during the upgrade process.

Software Files are available from GCSC or GSFS.com

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42PJ350 Dimensions

Power:			There must be at least 4 inches of Clearance on all sides
285W (Typical)
0.2W (Stand-By)						38-7/8"
						955.06mm
										4-9/16”
			11-7/16”							116mm
							15-3/4"
			290mm				400mm

27-1/8"
			Model No.
688.34mm					15-3/4"
			Serial No.		400mm
			Label
	24-5/6"
	617.22mm

3-15/16” 100mm

2-13/16" 71.43mm

Weight: 47.6 lbs with Stand 41.1 lbs without Stand

Remove 4 screws to remove stand for wall mount

2-3/16" 56mm

18-3/4" 476.25mm

2-3/16" 55.88mm

10-3/16" 259.08mm

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DISASSEMBLY SECTION

This section of the manual will discuss Disassembly, Layout and Circuit

Board Identification, of the 42PJ350 Advanced Single Scan Plasma Display Panel.

Upon completion of this section the Technician will have a better

understanding of the disassembly procedures, the layout of the printed circuit boards and be able to identify each board.

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Removing the Back Cover

To remove the back cover, remove the 32 screws Indicated by the arrows.

(The Stand does not need to be removed).

PAY CLOSE ATTENTION TO THE TYPE, SIZE AND LENGTH

Of the screws when replacing the back cover.

Improper type can damage the front.

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Circuit Board Layout

Identifying the Circuit Boards

C FP FPC

FPC

FPC

FPC

Board iveDr-Y

Y-SUS

Panel Voltage and Panel ID Label

FPC

Z-SUS

Power Supply (SMPS)

Z-SUB

Main Board

Control

FPC

C FP

		TCP
				AC In
						Side
Conductive Tape		Heat Sink				Input
						(part of
						main)

	Left “X”					Right “X”
				Conductive Tape
							Conductive Tape
IR/LED	Soft Touch
			Invisible Speakers
Board	Keypad

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42PJ350 Connector Identification Diagram

P201				PANEL
			p/n: EAJ60716204 (PDP42T10000.ADLGB)
		Y-DRIVE	p/n: EAJ60716215 (PDP42T10000.ADLGB)
		Board
		p/n: EBR63633601
P202			P811
		P206		SMPS
		P201
				POWER SUPPLY
P303				Board	Top row Odd
					Back row Even
		Y-SUS		p/n: EAY60912401	SC101
		Board				P813
P204					L N
		p/n: EBR63038301
				P163
			P101	n/c
		P101		P121 P102
P205	P106			CONTROL
		P211
		P209	p/n: EBR63632301	Board
				P161	P162
P206						AC
						In

	P233	LEFT X Board		p/n: EBR63628801			P211 P232	P331 P311	p/n: EBR63628701
P100	P201	P202	P203		P204	P205	P206	P301	P302	P303
P101
FRONT IR		Speakers (Front Right)			p/n: EAB60962801				p/n: EAB60962801
p/n: EBR65007704

Front “Soft Switch” Key Pad

		P2	Z-SUS
			Board	P4
		p/n: EBR63038801
		P1		P3
		p/n: EBR63634601		P2
				P1
	LVDS	Z-SUB Board
		P301	P703
			P900
		P704	n/c
			MAIN
		P801	Board
		p/n: EBT60953602
		RIGHT X Board
	P304	P305	P306

Speakers (Front Left)

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Disassembly Procedure for Circuit Board Removal

Note: 1) Remember to be cautious of ESD as some semiconductors are CMOS and prone to static failure.

Switch Mode Power Supply Board Removal

Disconnect the following connectors: P811, P813 and SC101. Remove the 8 screws holding the SMPS in place.

Remove the board. When replacing, be sure to readjust the Va/Vs voltages in accordance with the Panel

Label. Also, re-confirm

Y-SUS Board Removal	Note: The Y-SUS does not come with the connector to
	the Lower Y-Drive

Remove the Left Vertical Brace. 4 screws, 2 metal tap and 2 plastic tap.

Disconnect the following connectors: P201, P203, P206, P211 and Ribbon Cable P101. To remove P101, lift up on the locking mechanism and pull the ribbon cable out.

Remove the 16 screws holding the Y-SUS in place. Do not run the set with P211removed.

Remove the Y-SUS board. When replacing, be sure to readjust the Va/Vs voltages in accordance with the
Panel Label.
Confirm VSC, -Vy and Z	Note: The Y-SUS does not come with the connectors	Board Standoff
Y-Drive Board Removal	between the Y-SUS and Y-Drive
Disconnect P101~P106 Connectors to the Panel
Remove P106 by lifting up on the locking mechanism and pull the ribbon cable out.
Do not run the set with P106 connector removed.
Remove the 7 screws holding the Y-Drive board in place.		Collar
Lift up slightly, the slide to the left. Remove the Y-Drive Board.

Note: Y-SUS, Z-SUS and Y-Drive boards are mounted on board stand-offs that have a small collar.

The board must be lifted slightly to clear these collars. Behind each board are “Chocolate” (dense rubber like material) that act as shock absorbers. They may make the board stick when removing.

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Disassembly Procedure for Circuit Board Removal (2)

Z-SUS Board Removal

Disconnect the following connectors: P1 and P2, then P4 by pulling out the locking mechanism and pulling out the FPC to the panel. Note, slide a thin object (top side) between ribbon and connector to remove.

Remove the 9 screws holding the board in place.

Lift up slightly to clear the screw stand-offs and pull the Z-SUS upward to unseat P3/P2 from the Z-SUB board and remove the Z-SUS board.

When replacing, be sure to readjust the Va/Vs voltages in accordance with the Panel Label. Confirm VS, -Vy and Z-bias (VZB) as well.

Z-SUB Board Removal

Remove the two screws in the Z-SUB board. Remove P1 by pulling out the locking mechanism and pulling out the FPC to the panel, See note above concerning P4 removal. Pull down and remove Z-SUB.

Main Board Removal

Disconnect the following connectors: P703 LVDS and P301 (press gently inward on the locking tabs) and pull out, P704 and P801. Remove 1 screw in the decorative plastic piece and remove.

Remove the 4 screws holding the Main board in place and Remove the board.

Control Board Removal

Disconnect the following connectors: P121 LVDS, P101 Ribbon and P102. Then P161, P162 Ribbons by lifting up the locking tab. Remove the 1 screws holding the Control board in place. Lift up the bottom and pull down to unseat it from the two metal supports at the top and Remove the board. Pay attention to the top right back side of the board. There is a piece of rubber (Chocolate) that may fall off. Be sure to replace the rubber piece.

Front IR and Key Pad Removal

FRONT IR/INTELLIGENT SENSOR and POWER BUTTON:

Disconnect P100 and P101. Note: P101 is a ribbon connector. Lift up the locking mechanism and slide the ribbon cable out. Remove the Board by lifting up on the top tabs, lift the board and remove.

KEY PAD:

The Key Pad is a thin strip of static sensitive material attached to the front glass. It is not removable.

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X Drive Circuit Board Removal Continued

Make sure AC is removed.

Lay the Television down carefully on a padded surface.

Make sure to use at least two people for this process so as not to flex the panel glass.

a)Remove the Back Cover.

b)Remove the Stand (4 Stand Screws were removed during back removal).

c)	Disconnect the two connector on the left side of the Main board, P704 and P801.
d)	Remove the Stand Metal Support Bracket (5 Screws) 2 Plastic tap thread and 3 Metal thread.
e)	Remove the two Vertical support Braces marked “E”.
	Note: There are 4 Screws per/brace, 2 Plastic tap thread and 2 Metal thread.
	(Note, the right brace has a Grounding wire from the AC input which must also be removed).
f)	Remove the 7 screws holding the Heat Sink. (Warning: Never run the set with this heat sink removed).
	To remove the heat sink, lift up to release the tacky Chocolate (heat transfer material) and slide the
	heat sink to the left to clear the connector wires on the right side.
	Note: There are three large pieces of conductive tape on the heat sink that must be removed.
	Also, note that there several pieces of Chocolate heat transfer material attached all thethe wayway acrossacross thethe
	underside of the heat sink. There is a mark on either
	side of the tape on the heat sink which shows its locations.	Chocolate
		Heat transfer
X-DRIVE LEFT, AND X-DRIVE RIGHT REMOVAL:		material
		Heat sink

Disconnect all TCP ribbon cables from the defective X-Drive board and all other Ribbon cables going to the board.

Remove the (3 Left or Right X) or (5 Center X) screws holding the defective X-Drive board in place. Remove the board. Reassemble in reverse order. Recheck Va / Vs / VScan / -VY / Z-Drive.

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Getting to the X Circuit Boards

With Stand removed

E

Left E

Right

D

	Warning:
			C
	Never run the TV with the
	TCP Heat Sink removed	Ground
	F	Wire
	Heat Sink

D

B

Warning Shorting Hazard: Conductive Tape. Do not allow to touch energized circuits.

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Left and Right X Drive Connector Removal

See below to Remove the Connections on the X-Boards.

From the X-Boards to the Control Board. There may be tape on these connectors.

P232, P331

Are the same

Remove tape (if present) and Gently pry the locking mechanism upward and remove the ribbon cable from the connector.

Disconnect connector P233

Va from the Y-SUS to Left X Only

Connectors from Left and Right X Boards

P211 to P311

Left X to Right X

P211, P311

Are the same

	Carefully lift the TCP ribbon up and off.
	It may stick, be careful not to crack TCP.
Removing Connectors to the TCPs.	(See next page for precautions)

Gently lift the locking mechanism	TCP

upward on all TCP connectors

Left X: P201~206 Example Right X: P301~306

Cushion (Chocolate)

Flexible ribbon cable connector

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TCP (Tape Carrier Package) Generic Removal Precautions

The TCP has two small tabs on each side which lock the ribbon cable fully into the connector. They have to be lifted up slightly to pull the connector out.

Note: TCP is usually stuck down to the Chocolate heat transfer material, be Very Careful when lifting up on the TCP ribbon cable.

Lift up the lock as shown using your fingernail.

(The Lock can be easily broken. It needs to be handled carefully.)

Separate the TCP from the connector as shown.

TCP Film can be easily damaged.

Handle with care.

Tab

Tab

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Left and Right X Drive Removal

Remove the 4 screws in Left or Right X-Boards, (9 Total)

Shared with the

Right X

Shared with the

Left X

The Left X Board drives the Right 5/16 of the side of the screen vertical electrodes The Center X Board drives the Center 3/8 of the of the screen vertical electrodes

The Right X Board drives the Left 5/16 of the side of the screen vertical electrodes

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