AOC L1740 Service Manual

17" LCD Colour Monitor

SH4 HP L1740

Service

Service

Service

CJ6B50/76

CJ6B50/02

Horizontal frequencies 30 - 83 kHz

TABLE OF CONTENTS

Description	Page
Important Safety Notice---- --------------------------	2
Technical Data --------------------------------------	3~6
Installation/On Screen Display-------------------	7~10
Warning Message-------------------------------------	11
Factory Mode------------------------------------------	12
Flat Panel adjust--------------------------------------	13
Trouble shooting--------------------------------------	14
Mechanical Instructions-------------------------	15~16
Definition of pixel defects----------------------------	17
Electrical Instructions---------------------------	18~19
Failure mode of panel---------------------------------	20
Display adjustment-----------------------------------	21
Safety test requirements-----------------------------	22

	Description		Page
	DDC Instructions/DATA-------------------------		23~31
	ISP Instructions---------------------------------		32~34
	Repair tips/Repair Flow chart------------------		35~38
	Wiring Diagram---------------------------------------		39
	Function Block----------------------------------------		40
	Scaler Diagram----------------------------------		41~45
	Scaler Board C.B.A------------------------------		46~47
	Control Diagram & C.B.A.----------------------------		48
	Power Diagram ----------	.-----------------------	49~54
	---------------------------------------Exploded View		55
	Recommended/Spare	parts list----------------	56~58
	General product specification------------------		59~90
	Different parts list------------------------------------		91

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.

CAUTION: USE A SEPARATE ISOLATION TRANSFORMER FOR THIS UNIT WHEN SERVICING.

REFER TO BACK COVER FOR IMPORTANT SAFETY GUIDELINES

Published by BCU Monitors	Printed in Suzhou	Copyright reserved	Subject to modification F Nov .11 2004				GB 3138 106 10438

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HP L1740

Important Safety Notice

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Proper service and repair isimportant to the safe, reliable operation of all HPConsumer Electronics Company** Equipment. The service procedures recommended by HP and described in this service manual are effective methods of performing service operations. Some ofthese 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. HP 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, HP has not undertaken any such broad evaluation. Accordingly, a servicer who uses a service procedure or tool which is not recommended by HP 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, HP Consumer Electronics Company will bereferred to as HP.

WARNING

Critical components having special safety characteristics are identified with a bythe Ref. No. inthe parts list and

enclosed within a broken line*

(where several critical components are grouped in one area) along with the safety symbol on the schematics or

exploded views.

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 Philips. Philips assumes no liability, express or implied, arising out of any unauthorized modification of design.

Servicer assumes all liability. * Broken Line

FOR PRODUCTS CONTAINING LASER :

DANGERInvisible laser radiation when open.

AVOID DIRECT EXPOSURE TO BEAM. CAUTIONUse of controls or adjustments or

performance of procedures other than those specified herein may result in hazardous radiation exposure.

CAUTIONThe 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 moduleusing mounting holes arranged infour corners.

-Do not press onthe panel, edge of theframe strongly or electric shock as this will result in damage to the screen.

-Do not scratch orpress on the panel withany sharp objects, such as pencil or pen asthis may result in damage to the panel.

-Protect the module fromthe ESD as it maydamage the electronic circuit (C-MOS).

-Make certain that treatment person s body are grounded through wrist band.

-Do not leave themodule in high temperature andin areas of high humidity for a long time.

-Avoid contact with water as it may ashort circuit within the module.

-If the surface ofpanel become dirty, please wipe it off with a soft material. (Cleaning with a dirty or rough cloth may damage the panel.)

Technical Data

HP L1740

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"

4 HP L1740

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Technical Data(Continued)

2. Electrical characteristics and performance

Test signal and test method in accordance with test instructions sheet 161 of the product where applicable.

2.1 Actual display size: 337.920 x 270.336 mm

2.2 Resolution

1.Factory Preset modes (15 modes)

#

Resolution

H-Frequency

Pixel rate

V-Frequency

Comment

(Hz)

(MHz)

1

640X480

31.469K

25.175

59.940 Hz

VGA

2

640X480

37.861K

31.5

72.809 Hz

VESA

3

640X480

37.5K

31.501

75 Hz

VESA

4

720X400

31.469K

28.322

70.087 Hz

VGA

5

800X600

37.879K

40

60.317 Hz

VESA

6

800X600

48.077K

50

72.188 Hz

VESA

7

800X600

46.875K

49.498

75 Hz

VESA

8

832X624

49.726K

57.284

74.551 Hz

MAC

2.5

9

1024X768

48.363K

65

60.004 Hz

VESA

10

1024X768

56.476K

75

70.069 Hz

VESA

11

1024X768

60.023K

78.75

75.029 Hz

VESA

12

1152X870

68.68K

100

75.06 Hz

MAC

13

1152X900

71.71K

108

76.05 Hz

SUN

14

1280X1024

63.98K

108

60.02Hz

VESA

15

1280X1024

79.97K

135

75.02Hz

VESA

Over-scan Mode

16

640*480

43.269K

36.000

85.008Hz

Technical Data(continued)

HP L1740

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2.13

2.14

2.12

6 HP L1740

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Technical Data(Continued)

Installation

HPL 1740		7

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3. For analog operation, connect one end of the VGA signal

Rear Panel Components cable to the VGA connector on the monitor 1, and the other end to the VGA connector on the computer 2.

No	Component			Function
1	AC power connector			Connects the AC power cord to the monitor
2	USB downstream			connectors Connects optional USB devices
				to the monitor
3	USB upstream connector			Connects the USB cable to the host
				(computer or another USB hub)
4	DVI connector (available on			. Connects the DVI -D signal cable to the
	select models)			monitor
5	VGA connector			Connects the VGA cable to the monitor

Connecting the VGA Signal Cable

4. Connect the USB cable to the USB upstream connector on the monitor 1 and to a convenient USB connector on the computer 2.

Connecting the USB Cable

Connecting the Power Cable

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Front Pan el Controls

On Screen Display

No		Control	Function		BASIC OSD MENU LEVEL S
1		Auto Adjust	Activates the auto adjustment feature for optimum
			image
2		Menu	Opens the On-Screen Display (OSD) menu
3		–- (Minus)	If OSD is on, press to navigate backward through
			the OSD menu features and decrease adjustment
			levels.
			If OSD is off, press to enable the DVI signal input
			(available on select models)
4		+ (Plus)	If OSD is on, press to navigate forward through the
			OSD menu features and increase adjustment
			levels
			If OSD is off, press to enable the VGA signal input
5		Power	Turns the monitor on or off

On Screen Display

HPL 1740

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ADVANCED OSD MENU LEVELS

Analog Mode Menu

Menu Level 1	Menu Level 2			Menu Level 3					Factory Reset?
Brightness	ADJ Scale								Y (90)
Contrast	ADJ Scale								Y (80)
Image Control		Auto Adjustment			("Adjusting " message)				Y (no FD)
	Horizontal Position			ADJ Scale					Y (no FD)
	Vertical Position			ADJ Scale					Y (no FD)
	Clock			ADJ Scale					Y (no FD)
	Clock Phase			ADJ Scale					Y (no FD)
	Cancel
	Save and Return
Color	9300 K
	6500 K								Y(FD)
	Custom Color				Custom Color ADJ
	SRGB
	Cancel
	Save and Return
Language	Deutsch
	S. Chinese
	English								N (FD=English)
	Espanol
	Francais
	Italiano
	Nederlands
	Cancel
	Save and Return
Management	Power Saver				On / Off Selection				N (FD=ON)
	Power On Recall				On /	Off	Selection		N (FD=ON)
	Mode Display				On /	Off	Selection		N (FD=OFF)
	Power-On Status display				On /	Off	Selection		N (FD=ON)
	Sleep timer			Timer Set Menu					N (FD=0;OFF)
	Default Video Input				-Analog - VGA				N (FD = DVI)
				-Digital - DVI
	Serial Number			Display monitor s/n
	Basic Menu								N (FD=Basic)
	Cancel
	Save and Return
OSD Control	Horizontal OSD Position			ADJ Scale					N (FD=50)
	Vertical OSD Position			ADJ Scale					N (FD=50)
	OSD Timeout				ADJ Scale				N (FD=30)
	Cancel
	Save and Return
Information	Current Settings:
	Recommended Settings:
	Serial Number:
	Total Hours:
	Backlight Hours:
	Exit
Factory Reset	Yes
	No
Exit

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HP L1740

On Screen Display

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Digital Mode Menu

Menu Level 1

Menu Level 2

Menu Level 3

Factory Reset?

Brightness

ADJ Scale

Y (90)

Contrast

ADJ Scale

Y (80)

Color

9300 K

6500 K

Y (FD)

Custom Color

Custom Color ADJ

SRGB

Cancel

Save and Return

Language

Deutsch

S. Chinese

English

N (FD=English)

Español

Français

Italiano

Nederlands

Cancel

Save and Return

Management

Power Saver

On / Off Selection

N (FD=ON)

Power On Recall

On / Off Selection

N (FD=ON)

Mode Display

On /

Off

Selection

N (FD=OFF)

On /

Off

Selection

N (FD=ON)

Power-On Status Display

Sleep Timer

Timer Set Menu

Default Video Input

-Analog - VGA

N (FD = DVI)

-Digital - DVI

Display monitor s/n

Serial Number

Basic Menu

N (FD=Basic)

Cancel

Save and Return

OSD Control

Horizontal OSD Position

ADJ Scale

N (FD=50)

Vertical OSD Position

ADJ Scale

N (FD=50)

OSD Timeout

ADJ Scale

N (FD=30)

Cancel

Save and Return

Information

Current Settings:

Yes

Recommended Settings:

Serial Number:

Total Hours:

Backlight Hours:

Exit

Factory Reset

Yes

No

Exit

NOTE:

" "

Unless designated by “FD”, the original factory default settings are identical to the user Factory Reset function.

Warning Message

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Item	Attention Signals	Display Time	Condition
1	Input Signal out of Range		See section power saver
2	No Input Signal		See section power saver
3	Going to Sleep		See section power saver
4	Adjusting		Auto hot key or OSD menu function
5	OSD Lock out	3secs	Push menu key for 10 sec then display 3 sec WM "OSD Lock out"
6	Input Not Available		DVI (Analog) switch to Analog (DVI) without sync
7	Check Video Cable		See section power saver

Power saver

		Power Saver - On		Power Saver - Off					Note
Quit signal	with	1. System blank and show WM "Going
cable				1. System blank and show moving
		to Sleep" 3 sec then sleep.		WM "No Input Signal" always.
Disconnect cable
		1. System blank and show WM Check		1. System blank and show WM
		Video Cable 10 sec then moving about		"Check Video Cable" 10 sec then
		50 sec.		moving always.
		2. Show WM "Going to Sleep"3 sec then
		sleep.
		3.	If push any key in sleep mode, then
		repeat item 1 to 2.
Out of range - 1									H<29.5	or
		1. System blank and show moving WM		1. System blank and show moving			"		H>92 or
		"Input Signal out of Range " about 60		WM "Input Signal out of Range					90>H>82.5
		sec.		always.					or V<49 or
		2.	Show WM "Going to Sleep "3 sec						V>87	or
		then sleep.							Vtotal>=1200
		3.	If push any key in sleep mode, then
		repeat item 1to 2.
Out of range - 2			"		"				DownScaling
				1. Show moving WM		Input Signal			Ex.
		1. Show moving WM Input Signal out of
		Range " 60 sec.		out of Range "60 sec.					1280x1024
		2.	WM disappear after WM 60 sec.	2. WM disappear after WM 60 sec.					(Only	for
		3.	IF push any key then repeat 1-2.	3. IF push any key then repeat 1-2.					HPL1530)
Out of range -3		1. Show moving WM " Input Signal out		1. Show moving WM " Input Signal					85Hz
		of Range "60 sec.		out of Range"60 sec.
		2.	After moving WM 60 sec then show	2. After moving WM 60 sec then
		WM "Going to Sleep "3 sec then sleep.		show WM " Going to Sleep"3 sec
		3.	If push any key in sleep mode, then	then sleep.
		repeat item 1 to 2.		3. If push any key in sleep mode,
				then repeat item 1 to 2.

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Lock/Unlock,Aging, Service/Factory Mode

Front control panel

To Lock/Unlock OSD function

The OSD function can be locked by pressing MANU" 2 "button for more than 10 seconds, the screen shows following windows for 3 seconds. Everytime when you press MANU " 2 " Or AUTO "1 " button, this message Appears On the screen automatically.

The POWER" 5 "& INPUT" 3 " hotkey are still functional for

POWER and INPUT expectively while OSD locked.

Locked OSD function can be released by pressing MANU " 2 " button for more than 10 seconds. While press MANU button for OSD unlocked purpose, the screen will keep showing OSD LOCK OUT until OSD function unlocked and the windows screen automatically showed .

Fig.1

SERVICE MODE

Power off Press and hold the Manu "2" Power -> on " 5 " ,then Into the service mode. Press Manu " 2 " button to bring up OSD menu for confirmation as below:

Access Factory Mode

Power off on the monitor, To hold Auto " 1 "And

+ " + " " 4 " buttons at the same time ,

And press POWER

button to power on the monitor. Press MANU button to

bring up OSD menu for confirmation

Factory menu

Cursor can move on gray color area

BL	: Blacklevel value
SUB-BRI	: Brightness value range(Min Max)
SUB-CON	: Contrast value range(Min Mid Max)
SRGB-B	: Brightness of sRGB(Reserved)
SRGB-C	: Contrast of sRGB(Reserved)
Gain-m	: Minimum value of User Gain
Gain-M	: Maximum value of User Gain

AUTO-SUB : To do Auto color function when push" Up "key in white

	pattern
Panel Type	: If set this to 1,2,3,4,5 then system will force panel type
	to LG(QDI), CPT or AU). Set to other value will auto
	detect panel based on panel hardware.
SCALER	: Read/Write scaler register
NVRAM	: Read/Write eeprom address

Flat Panel Adjust

HP ADJUSTMENT PATTERN.EXE

VERSION: 2.00 Rev A

OPERATING SYSTEM(S):

Microsoft Windows 98

Microsoft Windows Millennium Edition (ME)

Microsoft Windows 2000

Microsoft Windows XP 32-bit Personal

Microsoft Windows XP 32-bit Professional

DESCRIPTION: This CD contains the HP Auto-Adjustment utility, which is a single pattern program designed to help improve the picture quality of your HP flat panel monitor.

Note: Do not use the following procedure if your flat panel monitor is using a DVI connector option.

To use the Adjustment pattern with your flat panel monitor:

1.Execute the auto-adjust function from the OSD main menu.

2.If the result is not satisfactory, start the "Adjustment pattern.exe" program and repeat step 1.

Image quality characteristics that can be improved:

-Fuzzy or unclear focus

-Ghosting, streaking or shadowing effects

-Faint vertical bars

-Thin horizontal scrolling lines

-Centering the picture

Note: To achieve optimal picture performance, it is recommended that you always set the operating system display mode to your flat panel's native resolution. See list below for reference.

14in. and 15in. flat panels = 1024x768

17in., 18in. and 19in. flat panels = 1280x1024 20in. and 21in. flat panels = 1600x1200

HP L1740

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14			HP L1740	Trouble shooting
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The following table lists possible problems, the possible cause of each problem, and the recommended solutions.

Problem	Possible Cause	Solution
Screen is blank.	Power cord is	Connect the power cord.
	disconnected.
	Power switch on front	Press the front panel power
	panel of the monitor is	button.
	turned off.
	Video cable is	Connect the video cable
	improperly connected.	properly. Refer to
		Setting Up the Monitor, for
		more information.
	Screen blanking utility is active.	Press any key on the
		keyboard or move the
		mouse to inactivate the
		screen blanking utility.
Image appears	Brightness and contrast	Press the Auto Adjust button
blurred, indistinct, or	are too low.	on the front panel. If this
too dark.		does not correct the image,
		press the Menu button to
		open the Basic OSD Menu,
		and adjust the brightness
		and contrast scales as
		needed.
Image is not	Position may need	Press the Menu button to
centered.	adjustment.	access the OSD menu.
		Select Image Control/
		Horizontal Position or
		Vertical Position to adjust the
		horizontal or vertical
		position of the image.
" Check Signal	Monitor video cable is	Connect the 15-pin monitor
Cable " is displayed	disconnected.	video cable to the VGA
on screen.		connector on the computer,
		or, if connected, check the
		DVI-D signal cable to the
		DVI connector on the
		computer, or the VGA to
		DVI-I cable to the VGA
		connector on the computer
		(DVI available on select
		models only). Be sure that
		the computer power is off
		while connecting the video
		cable.
Out of Range. Set	Video resolution and/or	Restart your computer and
Monitor to 1280 x	refresh rate are set	enter Safe Mode. Change
1024 @ 60Hz is	higher than what your	your settings to a supported
displayed on screen.	monitor supports.	setting (see "Factory Preset
		Display Modes "table in
		Appendix B). Restart your
		computer so that the new
		settings take effect.

14	Mechanical Instruction

HPL 1740

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Front view

Fig.1

Fig.6

Back view

Fig.2

Fig.7

Step 1.Remove the base

Remove the four screws as Fig.2.Fig.3

Fig.3

Step 2. Remove the front cover as Fig.4~8.

a. Use thin "I" type screwdriver to open the clicks on top sides as Fig.4

b .Use thin "I" type screwdriver to open the clicks on right side as Fig.5

c. Use thin "I" type screwdriver to open 4 clicks on left side as Fig.6

Fig.8

Step 3.Remove the back cover

Open the clicks and unscrew the screws as shown in Fig.8 and then remove the back cover as shown in Fig.9

Fig.4

Fig.5

Fig.9

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Mechanical Instruction

Step .4 Remove the Metal frame board

remove the screws and then pull the metal frame with the direction as shown in Fig.10 Fig.11

Fig.10

Power board

Fig.11

Control board

Step 5. Remove the control , scaler and power board

remove the screws and disconnect the connector as shown in Fig.11

In warranty, it is not allowed to disassembly the LCD panel, even the backlight unit defect.

Out of warranty, the replacment of backlight unit is a correct way when the defect is cused by backlight (CCFL,Lamp).

Definition of pixel defects

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LCD Monitor Quality and Pixel Policy

The TFT monitor uses high-precision technology, manufactured according to HP standards, to guarantee trouble-free performance. Nevertheless, the display may have cosmetic imperfections that appear as small bright or dark spots.

This is common to all LCD displays used in products supplied by all vendors and is not specific to the HP LCD. These imperfections are caused by one or more defective pixels or sub-pixels.

1.A pixel consists of one red, one green, and one blue sub-pixel.

2.A defective whole pixel is always turned on (a bright spot on a dark background), or it is always off (a dark spot on a bright background). The first is the more visible of the two.3. A defective sub-pixel (dot defect) is less

2. visible than a defective whole pixeland is small and only visible on a specific background.The HP display does

not have more than:

4.bright dots.

5.dark dots.

6.total bright and dark dots.

7.No more than two adjacent (less than 2.5 mm edge-to-edge) defective pixels. To locate defective pixels, the monitor should be viewed under normal operating conditions, in normal operating mode at a supported resolution and refresh rate, from a distance of approximately 50 cm (16 in.).HP expects that, over time, the industry will continue to improve its ability to produce LCDs with fewer cosmetic imperfections And HP will adjust guidelines as improvements are made.

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Electrical Instructions

Table1 Preset Mode Resolution

#	Resolution	H-Frequency	Pixel rate	V-Frequency	Comment
		(Hz)	(MHz)
1	640X480	31.469K	25.175	59.940Hz	VGA
2	640X480	37.861K	31.5	72.809Hz	VESA
3	640X480	37.5K	31.501	75Hz	VESA
4	720X400	31.469K	28.322	70.087Hz	VGA
5	800X600	37.879K	40	60.317Hz	VESA
6	800X600	48.077K	50	72.188Hz	VESA
7	800X600	46.875K	49.498	75Hz	VESA
8	832X624	49.726K	57.284	74.551Hz	MAC
9	1024X768	48.363K	65	60.004Hz	VESA
10	1024X768	56.476K	75	70.069Hz	VESA
11	1024X768	60.023K	78.75	75.029Hz	VESA
12	1152X870	68.68K	100	75.06Hz	MAC
13	1152X900	71.71K	108	76.05Hz	SUN
14	1280X1024	63.98K	108	60.02Hz	VESA
15	1280X1024	79.97K	135	75.02Hz	VESA

				(TABLE 1)
2.3	Input signal mode for over-scan modes
Table2 Over -scan Mode Resolution
#	Resolution	H-Frequency	Pixel rate	V-Frequency	Comment
		(Hz)	(MHz)
16	640X480	43.269K	36.000	85.008Hz	VESA
17	800x600	53.674K	56.250	85.061Hz	VESA
18	1024x768	68.677K	94.500	84.997Hz	VESA
19	1280x1024	91.146K	157.50	85.024Hz	VESA

Electrical Instructions

Use Minolta CA-110 for color coordinates and luminance check. Luminance is > 200 Nits in the center of the screen when brightness at 100% and contrast set to 100% at 6500 K color temperature.

3.4 Adjustment of WHITE-D for sRGB (B)

Apply a 1280*1024 / 60Hz signal with white pattern, then adjust the R, G, B SubGain, for the screen center, the 1931 CIE chromaticity (X, Y) co-ordinates and Y Luminance shall be:

	sRGB
x(center)	0.3127 0.02
y(center)	0.3291 0.02
Y (nits)	150 10

Use Minolta CA-110 for color coordinates and luminance check. Luminance is > 140 Nits in the center of the screen at sRGB color temperature.

3.5Adjustment of sRGB (B)

Apply sRGB test program, the monitor shall pass sRGB test compliance. (Note : For sRGB compliance , the monitor shall pass either max. Delta E less than or equal to 15 and average Delta E less than or equal to 10 )

3.6 DDC/CI Function Check (B)

Connect D-sub and DVI-D cable to the monitor. Apply DDC/CI test program, the monitor shall pass DDC/CI test compliance both for

VGA and DVI input.

3.7 USB Function Check (B)

Connecting cable from upstream port of the monitor to PC system with XP OS and attaching external USB devices to downstream ports of the monitor. Apply USB test program, the monitor shall pass USB test compliance.

3.8 Setting for leaving the Factory (B)

a).The OSD Controls shall have the following factory default values after finishing all the Adjustment.

1. Menu = Basic

2.Color = 6500K

3.Language = English

4.Power Saver = ON

5.Power On Recall = ON

6.Mode Display = OFF

7. Horizontal OSD Position = 50%

8. Vertical OSD Position = 50%

9. OSD Timeout = 30

10. Sleep Timer = OFF

11. Brightness = 90%

12. Contrast = 80%

b.) When adjustment is finished, monitor should be set to 6500K color.

c.) The monitor shall leave the factory with the power switch set to the OFF position

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20 HP L1740

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Failure Mode Of Panel

Quick reference for failure mode of LCD panel

this page presents problems that could be made by LCD panel.

It is not necessary to repair circuit board. Simply follow the mechanical Polarizer has bubbles instruction on this manual to eliminate failure by replace LCD panel.

Failure description	Phenomenon

Vertical block defect

Polarizer has bubbles

Vertical dim lines

Foreign material inside polarizer. It shows liner or dot shape.

Vertical lines defect (Always bright or dark)

Concentric circle formed

Horizontal block defect

Bottom back light of LCD is brighter than normal

Horizontal dim lines

Back light un-uniformity

Horizontal lines defect (Always bright or dark)

						Backlight has foreign material.
Has bright or dark pixel						Black or white color, liner or
						circular type

Display adjustment

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Alignment procedure

1. Turn on HP L1740 LCD monitor.

2.Turn on the Timing/pattern generator. See Fig.1 Resolution :1280x1024

Timing : H= 31.47KHz V=60Hz

3. Preset LCD color Analyzer CA-110

-Remove the lens protective cover of probe CA-A30.

-Set measuring/viewing selector to measuring position for reset analyzer.(zero calibration) as Fig.2

- Turn on the color analyzer (CA-110)

-Press 0-CAL button to starting reset analyzer. See Fig.3

Clear image

Measurement/viewing selector

Fig. 4

10.Setting pattern to full white picture.

11.Press menu " 2 " then select F, by " 3 " button.

12.Press menu " 2 " to bring up submenu as following windows.

Cover (black)

Measurement viewing selector

Fig. 1

Fig. 2

4.Access Factory Mode

Power off on the monitor,

To hold Auto " 1 "And

+ " + " " 4 " buttons at the same time ,

And press POWER

button to power on the monitor. Press MANU button to

bring up OSD menu for confirmation

Factory Mode Indicator

Note: after alignment, please reset OSD to user s mode for normal operation. Otherwise, the monitor won t entering power saving mode and showing full white picture all the time as no video signal supplied. To leave factory mode by restart the monitor.

5. Adjust OSD menu to lower position of screen (i.g. adjust V-position to value " 0 " at submenu of OSD Setting.

6.Setting Brightness and Contrast

-Adjust Brightness to value " 90".

-Adjust Contrast to value " 80" .

7.Switch light probe to Viewing position.

8.Move the Lens barrel forward or backward to get clear image as shown in Fig. 4

9. Switch light probe to Measuring position. It should be able to indicate

9300 K

13.Press MENU buttons to select R G B. Increase/decrease value by press or buttons until the X, Y co-ordinates as below:

X= 0.283+/- 0.020 Y= 0.297 +/-0.020

Y>= 200 nits

6500 K

14.Original Panel Color SRGB

15. X=0.3127+/-0.02 Y=0.3291+/-0.02 Y=150+/-10

Alignment hits: 1. R for x value, G for y value, B for Y value on the colour analyzer.

2.If the colour analyzer has been calibrated and preset

colour temperature in it. Please switch to correct setting in accordance with colour settings.

16.Gray scale checking

-Switch Timing/pattern generator to

Pattern: 64 gray scale

Timing: 1024 X 768 60Hz 63.98KHz

-Setting both Brightness 90% and Contrast to 80% (Value).

-Check black and white scale are visible clearly across the screen.

See Fig. 5

Fig. 5

Note: The bright scale will be saturated, if Y is too large. The dark scale will be invisible, if Y is too small. Re-alignment or review

22 HP L1740

Go to cover page

All units that are returned for service or repair must pass the original manufactures safety tests. Safety testing requires both

Hipot and Ground Continuity testing.

HI-POT TEST INSTRUCTION

1.Application requirements

1.1 All mains operated products must pass the Hi-Pot test as described in this instruction.

1.2 This test must be performed again after the covers have been refitted following the repair, inspection or modification of the product.

2. Test method

2.1 Connecting conditions

2.1.1 The test specified must be applied between the parallelblade plug of the mainscord and all accessible metal parts of the product.

2.1.2 Before carrying out the test, reliable conductive connections must be ensured and thereafter be maintained throughout the test period.

2.1.3 The mains switch(es) must be in the "ON" position.

2.2 Test Requirements

All products should be HiPot and Ground Continuity tested as follows:

Condition	HiPot Test for	HiPot Test for		Ground Continuity
	products where	products where		Test requirement
	the mains input	the mains input is
	range is Full	110V AC(USA
	range(or 220V	type)
	AC)
Test	2820VDC	1700VDC		Test current:
voltage	(2000VAC)	(1200VAC)		25A,AC
				Test time:
Test time	3 seconds	1 second		3 seconds(min.)
(min.)				Resistance
				required:
Trip	set at 100 uA	5 mA		<=0.09+Rohm,
current	for Max.			R is the
(Tester)	limitation; set			resistance of
	at 0.1 uA for			the mains cord.
	Min. Limitation
Ramp	set at 2
time	seconds
(Tester)

2.2.1 The minimum test duration for Quality Control Inspector must be 1 minute.

2.2.2 The test voltage must be maintained within the specified voltage + 5%.

2.2.3 There must be no breakdown during the test.

2.2.4 The grounding blade or pin of mains plug must be conducted with accessible metal parts.

3. Equipments and Connection

3.1. Equipments

For example :

-ChenHwa 9032 PROGRAMMABLE AUTO SAFETY TESTER

-ChenHwa 510B Digital Grounding Continuity Tester

-ChenHwa 901 (AC Hi-pot test), 902 (AC, DC Hi-pot test) Withstanding Tester

3.2. Connection

*Turn on the power switch of monitor before Hipot and Ground Continuity testing.

Clip

Clip

(ChenHwa 9032 tester)

Video cable

Connect the "video cable" or "grounding screw"

to the CLIP on your tester.

Grounding screw

Connect the power cord to the monitor.

Power outlet

4. Recording	(Rear view of monitor)

Hipot and Ground Continuity testing records have to be kept for a period of 10 years.

General

DDC Data Re-programming

In case the DDC data memory IC or main EEPROM which storage all factory settings were replaced due to a defect, the serial numbers have to be re-programmed" Analog DDC IC, Digital DDC IC & EEPROM".

It is advised to re-soldered DDC IC and main EEPROM from the old board onto the new board if circuit board have been replaced, in this case the DDC data does not need to be re-programmed.

Additional information

Additional information about DDC (Display Data Channel) may be obtained from Video Electronics Standards Association (VESA). Extended Display Identification Data(EDID) information may be also obtained from VESA.

DDC EDID structure

For Analog interface: Standard Version 3.0 Structure Version 1.2

For Digital inferface: Standard Version 3.0 Structure Version 1.3

System and equipment requirements

1. An i486 (or above) personal computer or compatible. 2. Microsoft operation system Windows 95/98.

3.EDID43016 release.EXE program.exe (in the(313cd8-10rom6 10103manual) as shown in Fig. 1 4. A/D Alignment kits (3138 106 10079):

inclusion : a. Alignment box x1 (as Fig. 2)

Fig.2

b.Printer cable x1

c.(D-Sub) to (D-Sub) cable x1

d.(DVI-D) to (D-Sub) cable x1 (as Fig. 3)

Note: The EDID301.EXE (Release Version 1.58 20000818)is a

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Fig.3

CD-ROM with EDID46.EXE

(DVI-D) to (D-Sub) cable

	HP L17402025		2753
	HP L2025

Go to cover page

Note: The alignment box has already build-in a batteries socket for Using batteries (9V) as power source. Pull out the socket by remove four screws at the rear of box. Please do not forget that remove batteries after programming. The energy of batteries can only drive circuits for a short period of time.

Fig.5

A/D Alignment Kits - Digital connection

Pin assignment

A. 15-pin D-Sub Connector

B. Input DVI -D Connector pin

Fig.4

24 HP L1740

Go to cover page

Configuration and procedure

There are 2 chips contained OSD string, serial number..etc on the circuit board, main EEPROM which storage all factory

settings,OSD string. DDC IC which storage 128byte EDID data(serial number ..etc.). Following descirptions are the connection and procedure for Analog and Digital DDC application, the main EEPROM can be re-programmed along with Analog/Digital IC by enable factory memory data write function on the DDC program (EDID3014.6 .EXE).

Initialize alignment box

In order to avoid that monitor entering power saving mode due to sync will cut off by alignment box, it is necessary to initialize

alignment box before running programming software edid46Release For (EDID301writing block.EXE)4 . Following steps show you the procedures and

connection.

Step 1: Supply 8~12V DC power source to the Alignment box by plugging a DC power cord or using batteries.

Step 2: Connecting printer cable and video cable of monitor as Fig. 6

Note 1: If the connection is improper, you will see the following error

message (as shown in Fig. 8) before entering the main menu. Meanwhile, the (read EDID) function will be disable. At this time, please make sure all cables are connected correctly and fixedly, and the procedure has been performed properly.

Fig.8

Method 2: After create a shortcut of EDID3014 6 .EXE

This is for initialize alignment box.

4.6	(as shown in Fig. 9) which
: Double click EDID301 icon

is on the screen of Windows Wallpaper.

Bring up main menu of EDID3014 6 as shown in Fig. 10. This is for initialize alignment box.

8-12v		Fig.10
	+
		4 6

Fig.9

Note 2: During the loading, EDID30146

will verify the EDID data which just

loaded from monitor before proceed any further function, once

the data structure of EDID can not be recognized, the following

Fig.6

error message will appear on the screen as below. Please

confirm following steps to avoid this message.

1.

The data structure of EDID was incorrect.

2.

DDC IC that you are trying to load data is empty.

3.

Wrong communication channel has set at configuration setup

windows.

4. Cables loosed or poor contact of connection.

Fig.7

You can copy the EDID46 to the hard disk and then execute the program with the same steps as above

HP L17402025

257

Go to cover page

Re-programming Analog DDC IC

Step 1: After initialize alignment box, connecting all cables and box as shown in Fig. 14

Step 3: Modify DDC data (verify EDID version, week, year) 1. Click (new function) icon from the tool bar, bring up Step 1 of 9 as shown in Fig. 18 .

EDID3014.6 DDC application provides the function selection and text change (select & fill out) from Step 1 to Step 9.

8-12V

+

Fig.18

Fig/14

Step 2: Read DDC data from monitor

1. Click icon as shown in Fig. 15 from the tool bar to bring up

Step 4: Modify DDC data (Monitor Serial No.)

the Channels "Configuration Setup" windows as shown in Fig. 16.

1. Click Next , bring up Fig. 19.

Fig.15

Fig.19

2. Select the DDC2BIas the communication channel. and "Enable Factory mode"

As shown in Fig. 16.

Fig.16

3.Click OK button to confirm your selection.

4.Click icon (Read EDID function) to read DDC EDID data from monitor. The EDID codes will display on screen as shown in Fig. 17.

Fig.17

2. Click Next , bring up Fig. 20.

Fig.20

HP L1740

Go to cover page

6. Click Next , bring up Fig. 24

3. Click Next , bring up Fig. 21.

Fig.24

Fig.21

4. Click Next , bring up Fig. 22

7. Click Next , bring up Fig. 25

Fig.25

Fig.22

5. Click Next , bring up Fig. 23

8. Click Next , bring up Fig. 26.

- Serial number can be filled up or be changed at this moment. - Click Finish to exit the Step window.

Fig.23

Fig.26

	HP L17402025		5
	HP L2025		277

Go to cover page

Step 5: Write DDC data

1. Configuration should be as Fig. 27.

Fig.27

2. Access Factory Mode

Power off on the monitor, To hold Auto " 1 "And

+ " + " " 4 " buttons at the same time ,

And press POWER

button to power on the monitor. Press MANU button to

bring up OSD menu for confirmation

3. Click (Write EDID) icon from the tool bar to write DDC data. Bring up "Writing 0%~100%, ready" a progressing bar on the left down corner.

4. Click (Read EDID) to confirm it.

5. You can confirm the S/N in the OSD also

press the menu and enter the management then you can see the S/N.

Step 6: Save DDC data

Sometimes, you may need to save DDC data as a text file for using in other IC chip. To save DDC data, follow the steps below:

1. Click (Save) icon (or click "file"-> "save as") from the tool bar And give a file name as shown in Fig. 29.

The file type is EDID3401.6 file (*.ddc) which can be open in WordPad.

By using WordPad, the texts of DDC data & table (128 bytes, hex code) can be modified. If DDC TEXTS & HEX Table are completely correct, it can be saved as .ddc flie to re-load it into DDC IC for DDC Data application.

46

Fig.29

2. Click . Save

Step 8: Exit DDC program

Pull down the File menu and select Exit as shown in Fig. 30.

46

Fig.30

NOTE: If the Edid46Release run in

Win 95/98with some problem, try to run it in win 2000,

but you should install the EDID_PORT_TOOL first. The other step is the same as described above.

28

Go to cover page

Re-programming Digital DDC IC

Step 1:Connecting all cables and alignment box as shown in

Fig. 31.

8-12

+

Fig.31

Step 2: Initialize alignment box

(Shortcut of EDID3014.6 .EXE on Windows Wallpaper already.) Double click EDID3014.6 icon (as shown in Fig. 32) which is on the screen of Windows Wallpaper.

Bring up main menu of EDID3014.6 as shown in Fig. 33.

Fig.32

Fig.33

4.6

Step 3: Read DDC data from monitor

1.Click icon from the tool bar to bring up the Channels Configuration Setup windows as shown in Fig. 34.

2.Select the DDC2BIas the communication channel.

and "Enable Factory mode"

3. Click OK button to confirm your selection.

Fig.34

4. Click icon (Read EDID function) to read DDC EDID data from monitor. The EDID codes will display on screen as shown in Fig. 35.

Fig.35

Step 4: Modify DDC data (verify EDID version, week, year) 1. Click (new function) icon from the tool bar, bring up Step 1 of 9 (Digital) as shown in Fig. 36 .

EDID4.6 DDC application provides the function selection and text change (select & fill out) from Step 1 to Step 9.

Fig.36

Fig.37

Fig.38