Dell S2721HGF Simplified Service Manual Download Page 13

  5. Trouble Shooting Instructions

Common problems

The following table contains general information about common monitor problems you 
might encounter and the possible solutions:

Common 

Symptoms

What You 

Experience

Possible Solutions

No Video/

Power LED off

No picture

• Ensure that the video cable connecting the 

monitor and the computer is properly connected 

and secure.

• Verify that the power outlet is functioning 

properly using any other electrical equipment.

• Ensure that the power button is depressed fully.

• Ensure that the correct input source is selected 

in the 

Input Source

 menu.

No Video/

Power LED on

No picture or no 

brightness

• Increase brightness and contrast controls via 

OSD.

• Perform monitor self-test feature check.

• Check for bent or broken pins in the video cable 

connector.

• Run the built-in diagnostics.

• Ensure that the correct input source is selected 

in the 

Input Source

 menu.

Missing Pixels

LCD screen has 

spots

• Cycle power on-off.

• Pixel that is permanently off is a natural defect 

   that can occur in LCD technology.

• For more information on Dell Monitor Quality 

  and Pixel Policy, see Dell Support site at: 

   

https://www.dell.com/pixelguidelines

.

Stuck-on Pixels LCD screen has 

bright spots

• Cycle power On-Off.

• Pixel that is permanently off is a natural defect  

   that can occur in LCD technology.

• For more information on Dell Monitor Quality 

   and PixelPolicy, see Dell Support site at: 

   

https://www.dell.com/pixelguidelines

.

Brightness 

Problems

Picture too dim 

or too bright

• Reset the monitor to factory settings.

• Adjust brightness and contrast controls via OSD.

Safety Related 

Issues

Visible signs of 

smoke or sparks

• Do not perform any troubleshooting steps.

• Contact Dell immediately.

Intermittent 

Problems

Monitor 

malfunctions on 

& off

• Ensure that the video cable connecting the 

monitor to the computer is connected properly 

and is secure.

• Reset the monitor to factory settings.

• Perform monitor self-test feature check to 

determine if the intermittent problem occurs in 

self-test mode.

Summary of Contents for S2721HGF

Page 1: ...ipment or products It is recommended that service engineers should have repairing knowledge experience as well as appropriate product training per new model before performing the service procedures NOTICE To avoid electrical shocks the products should be connected to an authorized power cord and turn off the master power switch each time before removing the AC power cord To prevent the product awa...

Page 2: ...xploded view diagram with list of items Front trim Panel Power button power key Mid cover Power mylar Power board Interface board Main chassis Back cover Stand OSD Joysick board OSD button Joystick button ...

Page 3: ...ctivity Diagram AC INPUT 110V 220V LED DRIVER POWER BOARD LCD PANEL 27 16 9 1920 1080 144Hz INTERFACE BOARD LCD1 HDMI1 4 HDMI1 DP1 DP1 2 Headphone out AC JACK LCD2 Function Key BD KB1 HDMI1 4 HDMI2 LED1 LED key Board ...

Page 4: ...move four screws for unlocking mechanisms No 1 4 screw size M4x8 Torque 10 11kgfxcm S4 2 3 4 1 Lift the rear cover up carefully Disconnect the function key cable and power key cable from the connectors of the interface board and then remove the rear cover 4 3 2 3 1 Put the rear cover on a protective cushion Use a Philips head screwdriver to remove 4pcs screws for unlocking the function key board w...

Page 5: ...cs screws for locking the bracket chassis module with the panel No 1 4 Screw size M3x0 5x2 8 Torque 5 6kgfxcm Move the bracket and then disconnect the LVDS cable and panel lamp cable from the connectors of the panel module then lift up the bracket and put it on a protective cushion S7 S8 S9 Lift up the panel module and pull out the front bezel for releasing the front bezel S11 Remove the middle be...

Page 6: ...se a Philips head screwdriver to remove screws for unlocking circuit boards and then release the panel lamp cable from the hook of the bracket 6pcs No 1 screw size M4x8 Torque 6 0 5kgfxcm No 2 7 screw size M3x7 5 Torque 6 0 5kgfxcm S13 Turn over the bracket chassis module Remove the Mylar from the hooks of the bracket S12 3 4 2 1 5 6 ...

Page 7: ...lips head screwdriver to tighten 6pcs screws for locking the circuit board then locate the panle lamp cable into the hook of the bracket No 1 screw size M4x8 Torque 7 0 5kgfxcm No 2 6 screw size M3x7 5 Torque 7 0 5kgfxcm 3 4 2 1 5 6 Panel preparation Take out 1pcs panel module from the carton then remove the protective film by tearing off the tapes and then examine the panel surface according to i...

Page 8: ...p cable to connect with the connector of the panel module then tear off the adhesive tape paper on the back of the cable and fix the lamp cable with 3pcs adhesive tapes Cover the long lamp connector with 1pcs black PVC tape then connect the power key cable with the board S11 S12 2 3 4 1 Adjust the bracket chassis module and then u se a Philips head screwdriver to tighten 4pcs screws for locking th...

Page 9: ...0 2kgfxcm S16 S17 Take 1pcs joystick key and 1pcs function key board assemble the joystick key with the function key board then press the joystick key to check if it work normally S14 Take 1pcs rear cover put the rear cover on a cushion foam for later assembling S15 1 3 4 2 Move the assembled rear cover with function key board close to the assembled unit then connect unction key cable to the conne...

Page 10: ...vide power supply and a video signal to the monitor then turn on the monitor for functionality check S20 S21 Use a Philips head screwdriver to tighten 4pcs screws for locking the rear cover with the assembled unit Paste 2pcs labels on the specific positions No 1 4 screw size M4x10 Torque 9 0 5kgfxcm S19 S18 2 3 4 1 Take 1pcs base assemble the base with the stand then use a screwdriver to tighten t...

Page 11: ...e power LED remains white Also depending upon the selected input one of the dialogs shown below will continuously scroll through the screen S2721HGF The display will go into Standby mode in 4 minutes www dell com support S2721HGF No DP Cable Dell 27 Gaming Monitor or S2721HGF The display will go into Standby mode in 4 minutes www dell com support S2721HGF No HDMI 1 Cable 1 Dell 27 Gaming Monitor o...

Page 12: ...nitor then goes into the self test mode 3 Press and hold Button 5 for 4 seconds system will pop OSD message select and press Button 1 A gray screen appears 4 Carefully inspect the screen for abnormalities 5 Move joystick Button 1 to right The color of the screen changes to red 6 Inspect the display for any abnormalities 7 Repeat steps 5 and 6 to inspect the display in green blue black white and te...

Page 13: ...Missing Pixels LCD screen has spots Cycle power on off Pixel that is permanently off is a natural defect that can occur in LCD technology For more information on Dell Monitor Quality and Pixel Policy see Dell Support site at https www dell com pixelguidelines Stuck on Pixels LCD screen has bright spots Cycle power On Off Pixel that is permanently off is a natural defect that can occur in LCD techn...

Page 14: ... setting Alternatively use a dynamically changing screensaver Product specific problems Problem What you experience Possible solutions Screen image is too small Image is centered on screen but does not fill entire viewing area Check the Aspect Ratio setting in the Display menu OSD Reset the monitor to factory settings Cannot adjust the monitor with the buttons on the front panel OSD does not appea...

Reviews: