Samsung 2494HS, 2494HSI, 2494HM Service manual

LCD-Monitor

Chassis : LS24KI

Model : 2494HS

2494HSI 2494HM

Manual

SERVICE

TFT-LCD Monitor Contents

1. Precautions

2. Product specications

3. Disassembly and Reassemble

4. Troubleshooting

5. Exploded View & Part List

6. Wiring Diagram

7. Schematic Diagram

2494HS / 2494HSI / 2494HM

Refer to the service manual in the GSPN (see the rear cover) for the more information.

Contents

1. Precautions .............................................................................................................. 1-1

1-1. Safety Precautions ......................................................................................................... 1-1

1-2. Servicing Precautions ..................................................................................................... 1-2

1-3. Static Electricity Precautions .......................................................................................... 1-2

1-4. Installation Precautions .................................................................................................. 1-3

2. Product specications ............................................................................................ 2-1

2-1. Feature & Specications ................................................................................................. 2-1

2-2. Spec Comparison to the Old Models .............................................................................. 2-2

2-3. Accessories .................................................................................................................... 2-3

2-4. Accessories (Sold separately) ........................................................................................ 2-3

3. Disassembly and Reassemble ............................................................................... 3-1

3-1. Disassembly (2494HS) ................................................................................................... 3-1

3-2. Disassembly (2494HS) ................................................................................................... 3-3

4. Troubleshooting ...................................................................................................... 4-1

4-1. Troubleshooting .............................................................................................................. 4-1

4-2. When the Power Does Not Turn On ............................................................................... 4-2

4-3. When a blank screen is displayed (Analog) ................................................................... 4-4

4-4. When a Blank Screen Is Displayed (DVI) ...................................................................... 4-7

4-5. Error Examples and Actions ......................................................................................... 4-10

4-6. Adjustment .................................................................................................................... 4-11

5. Exploded View & Part List ...................................................................................... 5-1

5-1. Exploded View (2494HS) ................................................................................................ 5-1

5-2. Parts List (2494HS) ........................................................................................................ 5-3

5-3. Exploded View (2494HM) ............................................................................................. 5-15

5-4. Parts List (2494HM) ...................................................................................................... 5-17

6. Wiring Diagram ........................................................................................................ 6-1

6-1. Wiring Diagram - Main Board ......................................................................................... 6-1

6-2. Wiring Diagram ............................................................................................................... 6-2

6-3. Connector Functions ...................................................................................................... 6-3

6-4. Cables ............................................................................................................................ 6-3

7. Schematic Diagram ................................................................................................. 7-1

7-1. Circuit Descriptions ......................................................................................................... 7-1

7-2. Schematic Diagram ....................................................................................................... 7-3

GSPN (Global Service Partner Network)

Area Web Site

North America http://service.samsungportal.com

Latin America http://latin.samsungportal.com

CIS http://cis.samsungportal.com

Europe http://europe.samsungportal.com

China http://china.samsungportal.com

Asia http://asia.samsungportal.com

Mideast & Africa http://mea.samsungportal.com

This Service Manual is a property of Samsung Electronics Co.,Ltd.

Any unauthorized use of Manual can be punished under applicable International and/or domestic law.

Printed in Korea P/N: BN82-00507A-01

1. Precautions

1-1. Safety Precautions

Follow these safety, servicing and ESD precautions to prevent damage and to protect against potential hazards such as electrical shock.

1-1-1. Warnings

For continued safety, do not attempt to modify the circuit board.

Disconnect the AC power and DC power jack before servicing.

1-1-2. Servicing the LCD Monitor

When servicing the LCD Monitor, Disconnect the AC line cord from the AC outlet.

It is essential that service technicians have an accurate voltage meter available at all times. Check the calibration of this meter periodically.

1-1-3. Fire and Shock Hazard

Before returning the monitor to the user, perform the following safety checks:

Inspect each lead dress to make certain that the leads are not pinched or that hardware is not lodged between the chassis and other metal parts in the monitor.

Inspect all protective devices such as nonmetallic control knobs, insulating materials, cabinet backs, adjustment and compartment covers or shields, isolation resistorcapacitor networks, mechanical insulators, etc.

Leakage Current Hot Check (Figure 1-1): WARNING : Do not use an isolation transformer during this test. Use a leakage current tester or a metering system that complies with American National Standards Institute (ANSI C101.1, Leakage Current for Appliances), and Underwriters Laboratories (UL Publication UL1410, 59.7).

(READING SHOULD) NOT BE ABOVE 0.5mA

DEVICE UNDER TEST

TEST ALL

EXPOSED METAL

SURFACES

2-WIRE CORD

*ALSO TEST WITH

PLUG REVERSED (USING AC ADAPTER PLUG AS REQUIRED)

With the unit completely reassembled, plug the AC line cord directly into a 120V AC outlet. With the unit’s AC switch

LEAKAGE CURRENT TESTER

EARTH

GROUND

Figure 1-1. Leakage Current Test Circuit

rst in the ON position and then OFF, measure the current between a known earth ground (metal water pipe, conduit,

etc.) and all exposed metal parts, including: metal cabinets, screwheads and control shafts. The current measured should not exceed 0.5 milliamp. Reverse the power-plug prongs in the AC outlet and repeat the test.

1-1-4. Product Safety Notices

Some electrical and mechanical parts have special safetyrelated characteristics which are often not evident from visual inspection. The protection they give may not be obtained by replacing them with components rated for higher voltage, wattage, etc. Parts that have special safety characteristics are identied by on schematics and parts lists. A substitute replacement that does not have the same safety characteristics as the recommended replacement part might create

shock, re and/or other hazards. Product safety is under review continuously and new instructions are issued whenever

appropriate.

1-1

1-2

1. Precautions

1-2. Servicing Precautions

WARNING: An electrolytic capacitor installed with the wrong polarity might explode. Caution: Before servicing units covered by this service manual, read and follow the Safety Precautions section of

this manual.

Note: If unforeseen circumstances create conict between the following servicing precautions and any of the

safety precautions, always follow the safety precautions.

1-2-1 General Servicing Precautions

Always unplug the unit’s AC power cord from the AC power source and disconnect the DC Power Jack before attempting to: (a) remove or reinstall any component or assembly, (b) disconnect PCB plugs or connectors, (c) connect a test component in parallel with an electrolytic capacitor.

Some components are raised above the printed circuit board for safety. An insulation tube or tape is sometimes used. The internal wiring is sometimes clamped to prevent contact with thermally hot components. Reinstall all such elements to their original position.

After servicing, always check that the screws, components and wiring have been correctly reinstalled. Make sure that the area around the serviced part has not been damaged.

Check the insulation between the blades of the AC plug and accessible conductive parts (examples: metal panels, input terminals and earphone jacks).

Insulation Checking Procedure: Disconnect the power cord from the AC source and turn the power switch ON. Connect an insulation resistance meter (500 V) to theblades of the AC plug. The insulation resistance between each blade of the AC plug and accessible conductive parts (see above) should be greater than 1 megohm.

Always connect a test instrument’s ground lead to the instrument chassis ground before connecting the positive lead; always remove the instrument’s ground lead last.

1-3. Static Electricity Precautions

Some semiconductor (solid state) devices can be easily damaged by static electricity. Such components are commonly

called Electrostatically Sensitive Devices (ESD). Examples of typical ESD are integrated circuits and some eld-effect

transistors. The following techniques will reduce the incidence of component damage caused by static electricity.

Immediately before handling any semiconductor components or assemblies, drain the electrostatic charge from your body by touching a known earth ground. Alternatively, wear a discharging wrist-strap device. To avoid a shock hazard, be sure to remove the wrist strap before applying power to the monitor.

After removing an ESD-equipped assembly, place it on a conductive surface such as aluminum foil to prevent accumulation of an electrostatic charge.

Do not use freon-propelled chemicals. These can generate electrical charges sufcient to damage ESDs.

Use only a grounded-tip soldering iron to solder or desolder ESDs.

Use only an anti-static solder removal device. Some solder removal devices not classied as “anti-static” can generate electrical charges sufcient to damage ESDs.

Do not remove a replacement ESD from its protective package until you are ready to install it. Most replacement ESDs are packaged with leads that are electrically shorted together by conductive foam, aluminum foil or other conductive materials.

Immediately before removing the protective material from the leads of a replacement ESD, touch the protective material to the chassis or circuit assembly into which the device will be installed. Caution: Be sure no power is applied to the chassis or circuit and observe all other safety precautions.

Minimize body motions when handling unpackaged replacement ESDs. Motions such as brushing clothes together,

or lifting your foot from a carpeted oor can generate enough static electricity to damage an ESD.

1-3

1. Precautions

1-4. Installation Precautions

For safety reasons, more than two people are required for carrying the product.

Keep the power cord away from any heat emitting devices, as a melted covering may cause re or electric shock.

Do not place the product in areas with poor ventilation such as a bookshelf or closet. The increased internal

temperature may cause re.

Make sure to turn the power off and unplug the power cord from the outlet before repositioning the product. Also check

the antenna cable or the external connectors if they are fully unplugged. Damage to the cord may cause re or electric

shock.

Keep the antenna far away from any high-voltage cables and install it rmly. Contact with the highvoltage cable or the

antenna falling over may cause re or electric shock.

When installing the product, leave enough space (10cm) between the product and the wall for ventilation purposes.

A rise in temperature within the product may cause re.

1. Precautions

Memo

1-4

2. Product specications

2-1. Feature & Specications

Model 2494HS / 2494HSI / 2494HM

Support PC / DVI / HDMI

�

DC DC 50000:1 Applied

�

Adopted two 3W speakers.

�

USB (1 up, 2 down) optional

�

HDCP Applied for HDMI/DVI-D Fixed Aspect Ratio Support

�

Supports xed horizontal and vertical ratios

�

Supported camera effects: Black/Sepia/Green/Blue

�

Supports the Off-timer function

�

Item Description

Model 2494HS / 2494HSI 2494HM

2. Product specications

Feature

Specications

LCD Panel TFT-LCD panel, RGB vertical stripe,

normally black transmissive,

23.6-Inch viewable, 0.2715(H)x0.2715(V) mm pixel pitch

Scanning Frequency Horizontal: 30 kHz ~ 81 kHz (Automatic)

Vertical: 56 Hz ~ 60 Hz

Maximum Resolution Horizontal: 1920 Pixels

Vertical: 1080 Pxels

Input Signal

Input Sync Signal Seperate H/V sync, Composite:

Maximum Pixel Clock Rate

Active Display Horizontal/Vertica

AC Power Voltage & Frequency AC 90~264V Volts, 60/50Hz

Power Consumption Less than 48W Less than 48W

Dimensions ( W X H X D) 572.8 x 227.4 x 420.4 mm (With Stand)

PC/DVI/HDMI

automatic synchronization without external switch

Level : TTL level (V high ≥ 2.0V, V low ≤ 0.8V)

164MHz

l 521.28(H) x 293.22(V) mm 531.36(H) x 298.89(V) mm

572.8 x 67.5 x 363.4 mm (Without Stand)

TFT-LCD panel, RGB vertical stripe, normally black transmissive,

24-Inch viewable, 0.2768(H)x0.2768(V) mm pixel pitch

572.8 x 249.9 x 420.4 mm (With Stand)

572.8 x 67.5 x 363.7 mm (Without Stand)

Weight

Environmental

Considerations

Note: Designs and specications are subject to change without prior notice..

Products: 6.2 kg Products: 8.4 kg

Operating Temperature: 10˚C ~ 40˚C(50˚F ~ 104˚F)

Operating Humidity: 10% ~ 80%

Storage temperature: -20˚C ~ 45˚C(-4˚F ~ 113˚F)

Storage Humidity: 5% ~ 95%

2-1

2-2

2. Product specications

2-2. Spec Comparison to the Old Models

Model 2494HS / 2494HSI 2494HM 2493HM

Design

Screen Size 23.6” 24” 24”

Display Size 16:9 16:9 16:10

Brightness 300cd/m2 300cd/m2 400cd/m2

Dynamic CR 50000:1 50000:1 10000:1

Input Source Analog/Digital/HDMI Analog/Digital/HDMI Analog/Digital/HDMI

Speaker 3Wx2 3Wx2 2Wx2

Magictune Premium Premium Premium

Gamma

MagicBright

Color Tone

3 steps

Mode1 / Mode2 / Mode3

7 steps (Text / Internet / Game

/ Sports / Movie / Dynamic CR /

Custom)

4 Step

Cool / Normal / Warm / Custom

Mode1 / Mode2 / Mode3

7 steps (Text / Internet / Game

/ Sports / Movie / Dynamic CR /

Cool / Normal / Warm / Custom

3 steps

Custom)

4 Step

3 steps

Mode1 / Mode2 / Mode3

7 steps (Text / Internet / Game

/ Sports / Movie / Dynamic CR /

Custom)

4 Step

Cool / Normal / Warm / Custom

2-3

2. Product specications

2-3. Accessories

Product Description Ccde. No Remark

Quick Setup Guide BH68-00174P

Warranty Card

(Not available in all locations)

User’s Guide,

Monitor Driver,

Natural Color software,

MagicTune™ software

D-Sub(15 Pin) Cable

(Shipped as assembled with the set)

Power Cord 3903-00212

USB Cable(USB HAS stand only) BN39-00397C

2-4. Accessories (Sold separately)

Product Description Ccde. No Remark

BH68-01146A

BN59-00660F

BN39-00244G

Samsung Electronics

Service center

DVI Cable BN39-00246K

Samsung Electronics

Service center

2. Product specications

Memo

2-4

3. Disassembly and Reassemble

This section describes the disassembly and reassembly sequences for this monitor.

WARNING: As this monitor has parts that are sensitive to static electricity, be careful when handling them.

3-1. Disassembly (2494HS / 2494HSI)

Cautions: 1. Turn the monitor off before beginning the disassembly process.

2. Disassemble the monitor carefully as directed in the following procedures.

3. When disassembling the monitor, do not use any metal tools except for the provided jig.

Part Description Picture Description Screws

1. Place a soft cloth on the table and place the monitor on it so the front part is facing downwards. Hold and pull the stand downwards to remove it from the monitor set.

Stand

Rear cover

2. Remove the four (4) screws on the

bottom, as shown in the gure on the

right.

3. Hold the projected part of the rear cover with one hand, hold the front cover with the other hand, and then lift and remove the rear cover upwards.

Caution : If you remove the rear

cover by holding and lifting the red circle part marked with ‘NO’ upwards (to the

left of the gure on the

right), a crack may occur on the Function-PCB connector. Make sure to hold and lift the red circle part marked with ‘YES’ upwards (to the right of

the gure on the right), to

remove the rear cover.

YESNO

If handled

incorrectly, a crack may occur on the

Function-PCB

connector.

3-1

3-2

3. Disassembly and Reassemble

Part Description Picture Description Screws

4. Remove the shield lamp using a at

SHIELD-

LAMP

screwdriver or the provided jig.

Caution : Be careful because the

shield lamp is sharp.

Removing the cables

ASSY

CHASSIS

5. Remove the lamp wire, function wire, speaker connector, and LVDS cable connected to the chassis.

6. Remove the four (4) hex screws on the bottom of the shield, as shown in

the gure on the right.

7. Remove the eight (8) screws

designated in the gure on the right,

lift the boards upwards and remove

the cable shown in the gure on the

right.

BOARD, IP-Board

MAIN

8. Remove the main board and IP-board from the shield cover.

3-3

3. Disassembly and Reassemble

3-2. Disassembly (2494HS)

Cautions: 1. Turn the monitor off before beginning the disassembly process.

2. Disassemble the monitor carefully as directed in the following procedures.

3. When disassembling the monitor, do not use any metal tools except for the provided jig.

Part Description Picture Description Screws

1. Place a soft cloth on the table and place the monitor on it so the front part is facing downwards. Remove the four (4) screws

designated in the gure on the right

and remove the stand.

Caution : When removing the screws,

make sure to hold the stand body with one hand so that the stand does not fall over.

Stand

Rear Cover

2. Remove the four (4) screws on the

bottom, as shown in the gure on the

right.

3. Hold the projected part of the rear cover with one hand, hold the front cover with the other hand, and then lift and remove the rear cover upwards.

Caution : If you remove the rear

cover by holding and lifting the red circle part marked with ‘NO’ upwards (to the

left of the gure on the

right), a crack may occur on the Function-PCB connector. Make sure to hold and lift the red circle part marked with ‘YES’ upwards (to the right of the

right gure) to remove the

rear cover.

YESNO

If handled

incorrectly, a crack may occur on the

Function-PCB

connector.

3. Disassembly and Reassemble

Part Description Picture Description Screws

4. Remove the shield lamp using a at

SHIELD-

LAMP

screwdriver or the provided jig.

Caution : Be careful because the

shield lamp is sharp.

Removing the cables

ASSY

CHASSIS

MAIN BOARD, IP-Board

5. Remove the lamp wire, function wire, speaker connector, and LVDS cable connected to the chassis.

6. Remove the four (4) hex screws on the bottom of the shield, as shown in

the right gure.

7. Remove the eight (8) screws

designated in the right gure, lift the

boards upward and remove the cable

shown in the gure on the right.

8. Remove the main board and IP-board from the shield cover.

※Reassembly procedures are in the reverse order of disassembly procedures.

3-4

4. Troubleshooting

4-1. Troubleshooting

Before troubleshooting, setup the PC ‘s display as below.

• Resolution: 1920 x 1080

• H-frequency: 75 kHz

• V-frequency: 60 Hz

If no picture appears, make sure the power cord is correctly connected.

Check the following circuits.

• No raster appears: Function PBA. Main PBA. IP-Board

• 5V develop but no screen : Main PBA

• 13V, 5V does not develop: IP-Board, Main PBA

4. Troubleshooting

4-1

4-2

4. Troubleshooting

4-2. When the Power Does Not Turn On

The LED on the front panel of the monitor does not work when the power is connected and the

Symptom

Major checkpoints

Power button is pressed.

Check if the Power switch on the rear panel of the monitor has been turned on.

Check the SMPS fuse and the IP-Board output power.

Check the connection between the IP-Board and the Main Board inside the monitor.

Check the power part of the Main Board and check if a similar symptom appears at another

output terminal.

CN600

IC203

Main Board Front

Diagnostics

Check the connection status of the

Function assy.

Can DC 5V be measured on pins 6, 7

of the CN600 connector when pins 3, 4,

and 5 are 0V?

Yes

Can DC 3.3V be measured on pin 3 of

the IC203 when pin 1 is DC 5V?

Yes

Check and replace the main board

related to the scaler.

Caution Make sure to disconnect the power before working on the IP board.

Replace the IP board.

Check the circuits related to

the IC203.

4-3

4. Troubleshooting

4-2-1. Circuit Diagram and Waveform for Power Failures

+ 39 hidden pages