Dell U2722DX User manual

Version: 01
Date: 2021/10/30
Service Manual - U2722D/DX

Product Announcement:
This product is certificated to meet RoHS
Directive and Lead-Free produced definition.
Using approved critical components only is
recommended when the situation to replace
defective parts. Vender assumes no liability
express or implied, arising out of any unauthorized
modification of design or replacing non-RoHS
parts. Service providers assume all liability.
Qualified Repairability:
Proper service and repair is important to the safe,
reliable operation of all series products. The
service providers recommended by vender should
be aware of notices listed in this service manual in
order to minimize the risk of personal injury when
perform service procedures. Furthermore, the
possible existed improper repairing method may
damage equipment 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 away from water or
expose in extremely high humility environment.
! To ensure the continued reliability of this
product, use only original manufacturer’s
specified parts.
! To ensure following safety repairing behavior, put
the replaced part on the components side of
PWBA, not solder side.
! To ensure using a proper screwdriver, follow the
torque and force listed in assembly and
disassembly procedures to unscrew screws.
! Using Lead-Free solder to well mounted the
parts.
! The fusion point of Lead-Free solder requested in
the degree of 220°C.
1. Important Safety Notice

2. Exploded view diagram with list of items
NOTE:
For replacement of power cord, connectivity cable and external power supply (if applicable), contact Dell:
1. Go to https://www.dell.com/support.
2. Verify your country or region in the Choose A Country/Region drop-down menu at the bottom-right corner of the page.
3. Click Contact Us next to the country dropdown.
4. Select the appropriate service or support link based on your need.
5. Choose the method of contacting Dell that is convenient for you.
15
14 16
13
Item Description Q'ty Remark
1 1
For EMEA Only, not for
other regions
2
Safety Mylar
1
13
4 1
15
6
IF BD
1
1 7
8 1
9
10
11 1
1
Joystick BD
12
1 13
1 14
USB BD
Panel
Key BD
Power BD
ASSY Chassis
1
1
15 1
1
ASSY Rear Cover
16
See “NOTE”
See “NOTE”
ASSY RISSER
See “NOTE”
See “NOTE”
USB-C 1.0 M cable (A to C)
HDMI 1.8 M cable (U2722DX Only)
Power cable
DisplayPort 1.8 M cable(U2722D Only)
ASSY BASE
ASSY Middle Frame

3. Wiring Connectivity Diagram

4. How to connect and disconnect power cable/ connectivity cable
WARNING: To change power cable/ connectivity cable, switch off power before unplugging the cable and replugging in required
cable.

4. How to connect and disconnect power cable/ connectivity cable

5. Disassembly and Assembly Procedures
5.1 Disassembly Procedures:
Tool Required:
List the type and size of the tools that would typically can be
used to disassemble the product to a point where components
and materials requiring selective treatment can be removed.
Tool Description:
- Screwdriver(Phillip head) #1
- Screwdriver(Phillip head) #2
- Penknife
- Soldering iron and absorber
NOTE:
This “Disassembly and Assembly Procedures” is for EMEA only,
not for other regions. Please note that Dell will deem warranty void
if any disassembly is done on the monitors.
S3
S2
S1
S1
Remove the monitor stand base:
1. Place the monitor on a soft cloth or cushion.
2. Press and hold the stand-release button.
3. Lift the stand up and away from the monitor.
S6
Wedge your fingers between rear cover and the
middle bezel on the corners of the top side of the
monitor to release the rear cover, then use one hand
to press the middle bezel, the other hand to pull up
carefully the rear cover in order of arrow preference
for unlocking mechanisms of rear cover.
S4
Use a Philips-head screwdriver to remove 4pcs
screws for unlocking mechanisms. Remove DP cap.
(No.1~4 screw size=M4x11; Torque=11±1kgfxcm)
Lift the rear cover up carefully. Disconnect the
joystick key cable and Usb EDP cable from the
connectors of the interface board, and then remove
the rear cover.
Use a Philips-head screwdriver to remove 2pcs
screw for unlocking the key board, then tear off the
tapes and release the key board.
(No.1~2 screw size=M2x2.4, Torque=0.8~1kgfxcm)
23
41
3
2
1
2
1
2
S5
Use a Philips-head screwdriver to release one screw
for unlocking the USB board, then release the USB
board from the hooks of the middle bezel and then
remove the USB board unit.
(No.1screw size=M3x6, Torque=4±0.5kgfxcm)
1
Tear off 1pcs aluminum foil for unfixing the bracket,
and then disconnect the LED cable from the
connector of the interface board.
S7

5. Disassembly and Assembly Procedures
S10
S9
S11
S12
S8
Use a Philips-head screwdriver to remove 13pcs
screws for unlocking the middle bezel with the panel
module.
(No.1~13 screw size=M3x5, Torque=5±0.5kgfxcm)
3
11 10
13 12
8
2
9
4
5761
Disconnect the panel lamp from the connector of the
panel, then release the panel lamp cable from the
hooks of the middle bezel.
Tear off the tape on the back of panel module for
releasing the LED cable, then
middle bezel, and put it on a cushion foam, and then
tear off the mylar tape for releasing the LED board.
lift up and take away the
U
.
se a Philips-head screwdriver to remove 4pcs
screws for unlocking the bracket chassis module
with the panel
(No.1~4 Screw size= M3x5, Torque=5±0.5kgfxcm)
4
1
11
Move up the bracket, then push the earing-lock and
disconnect the LVDS cable away from the connectors
of the panel module.
Take away the bracket chassis module and then put
the bracket chassis module on a protective cushion.
S13

5. Disassembly and Assembly Procedures
Use a Philips-head screwdriver to remove
screws for interface board and power board.
6pcs
(No.1 screw size=M4x8, Torque=7±1kgfxcm;
No.2~6 screw size=M3x7.5, Torque=7±1kgfxcm)
S15
Remove the power board board and interface
board from the
disconnect all of the cables.
bracket chassis module carefully,
and then
Remove the Mylar tape from the hooks of the
bracket.
S14
S16
1
3
4
2
65

5. Disassembly and Assembly Procedures
Turn over a power board and put the power board
into the bracket chassis, locate the panel power
cable into the hook of the bracket chassis module.
Place a bracket chassis base on a protective
cushion, then stick 3pcs Silicon sheets on the
positions as the picture below shown.
5.2 Assembly Procedures:
S2
S1
Take a black mylar to insert the hooks of the bracket
to cover the power board, then tear off the gum
paper of the panel lamp cable.
S4
Take a interface board, connect 1pcs LVDS cable and
1pcs EDP cable to the connectors of the interface
board, then connect the cable of the power board with
interface board. Turn over the interface board and
locate the board and EDP cable into the bracket. Use
a Philips-head screwdriver to tighten 6pcs screws for
locking the interface board and power board.
(No.1 screw size=M4x8, Torque=7.5±0.5kgfxcm;
No.2~6 screw size=M4x8, Torque=7.5±0.5kgfxcm)
S3
Panel preparation: Take out 1pcs panel module from
the carton, remove the protective film by tearing off
the tapes, then examine the panel surface according
to inspection criteria of the panel. Turn over the
panel module to place the screen faced down for
later assembling.
S5
Move the bracket chassis module close to the panel
module, then connect the LVDS cable to the
connector of the panel module, then turn over the
bracket chassis and put it on the back of the bracket
chassis module.
S6
1
3
4
2
65

5. Disassembly and Assembly Procedures
S8
Adjust the bracket chassis module, and then u
.
se a
Philips-head screwdriver to tighten 4pcs screws for
locking the bracket chassis module with the panel
(No.1~4 Screw size= M3x5, Torque=5±0.5kgfxcm)
S10
S7
Take 1pcs LED key board and 1pcs middle bezel,
then put the middle bezel into a fixture jip to fix the
middle bezel. Tear off the gum on the back of the
board, and then paste the LED board on the correct
position of the middle bezel, then paste 1pcs mylar
tape to cover the LED board as the picture below
shown.
Move the middle bezel with the LED board close to
the panel unit, then assemble the middle bezel with
the front bezel and panel module.
S11
4
1
11
Locate the panel lamp cable into the hooks of the
middle bezel, then connect the panel lamp cable to
connector of the panel module.
Tear off the release paper of the adhesive tape on
the back of the LED cable, then fix the LED cable on
the back of the panel module.
S9
S12
Use a Philips-head screwdriver to tighten 13pcs
screws for locking the middle bezel with the panel
module.
(No.1~13 screw size=M3x5, Torque=5±0.5kgfxcm)
3
11 10
13 12
8
2
9
4
5761

5. Disassembly and Assembly Procedures
S13
Take 1pcs USB board and 1pcs conductive foam.
Paste the conductive foam on the back of the USB
board, and then locate the USB board into the
correct position of the middle bezel. Use a Philips-
head screwdriver to tighten 1pcs screw for locking
the USB unit with the middle bezel.
(No.1 screw size=M3x6, Torque=4±0.5kgfxcm)
S14
Move the assembled rear cover close to the panel
unit, then connect the joystick key cable to the
connector of interface board. Connect the EDP
cable to the connector of the USB board. Put
down the rear cover and push the rear cover on
the positions marked as the picture below shown
for mechanisms engagement.
S16
Take 1pcs joystick key and 1pcs OSD board,
assemble the joystick key with the OSD board.
Locate the board to the correct position of the rear
cover, then use a Philips-head screwdriver to tighten
2pcs screws for locking the board with rear cover.
Tear off the tape papers on the back of the cable,
and then fix the key cable with tapes.
(No.1~2 screw size=M2x2.4, Torque=0.9±0.1kgfxcm)
S15
1
2
Connect the LED cable to connector of the interface
board, then paste 1pcs aluminum foil to fix the bracket
on the specific position as the picture below shown.
1

5. Disassembly and Assembly Procedures
Take a stand base close to the monitor. Fit the two
tabs on the upper part of the stand into the grooves,
and then lower the stand so that the monitor
mounting area snaps onto the stand.
Lift up the monitor to check the gap between the
front bezel and the panel, then provide power supply
and a video signal to the monitor , then turn on the
monitor for functionality check.
S18
S19
Use a Philips-head screwdriver to tighten 4pcs
screws for locking the rear cover with the unit. Stick
two pieces of label on the specific positions, then
insert a DP out Cap into the DP out connector.
(No.1~4 screw size=M4x11; Torque=11±1kgfxcm)
S17
23
41

6. Trouble Shooting Instructions
Self-Test
Your monitor provides a self-test feature that allows you to check whether your
monitor is functioning properly. If your monitor and computer are properly connected
but the monitor screen remains dark, run the monitor self-test by performing the
following steps:
1. Turn o both your computer and the monitor.
2. Unplug the video cable from the back of the computer. To ensure proper Self-Test
operation, remove all digital and the analog cables from the back of computer.
3. Turn on the monitor.
The floating dialog box should appear on-screen (against a black background), if the
monitor cannot sense a video signal and is working correctly. While in self-test mode,
the power LED remains white. Also, depending upon the selected input, one of the
dialogs shown below will continuously scroll through the screen.
No DP Cable
The display will go into Standby Mode in 4 minutes.
www.dell.com/U2722D/DX/DE
or
No HDMI Cable
The display will go into Standby Mode in 4 minutes.
www.dell.com/U2722D/DX/DE
4. This box also appears during normal system operation if the video cable
becomesdisconnected or damaged.
5. Turn o your monitor and reconnect the video cable; then turn on both your
computer and the monitor.
If your monitor screen remains blank after you use the previous procedure, check your
video controller and computer, because your monitor is functioning properly.

6. 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.

6. Trouble Shooting Instructions
Common
Symptoms
What You
Experience
Possible Solutions
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.
Missing Color Picture missing
color
• Perform monitor self-test.
• Ensure that the video cable connecting the
monitor to the computer is connected properly
and is secure.
• Check for bent or broken pins in the video cable
connector.
Wrong Color Picture color
not good
• Try dierent Preset Modes in Color settings
OSD.
• Adjust R/G/B value under Custom Color in Color
menu OSD.
• Change the Input Color Format to RGB or
YCbCr in the Color settings OSD.
• Run the built-in diagnostics.
Image retention
from a static
image left on
the monitor for
a long period of
time
Faint shadow
from the static
image displayed
appears on the
screen
• Set the screen to turn o after a few minutes
of screen idle time. These can be adjusted in
Windows Power Options or Mac Energy Saver
setting.
• Alternatively, use a dynamically changing
screensaver.

6. Trouble Shooting Instructions
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
appear on the
screen
• Turn o the monitor, unplug the monitor power
cable, plug it back, and then turn on the monitor.
No Input Signal
when user
controls are
pressed
No picture, the
LED light is
white
• Check the signal source. Ensure the computer
is not in the power saving mode by moving the
mouse or pressing any key on the keyboard.
• Check whether the signal cable is plugged
in properly. Connect the signal cable again, if
necessary.
• Reset the computer or video player.
The picture
does not fill the
entire screen
The picture
cannot fill the
height or width
of the screen
• Due to dierent video formats (aspect ratio) of
DVDs, the monitor may display in full screen.
• Run the built-in diagnostics.
No image
when using DP
connection to
the PC
Black screen • Verify which DP standard (DP 1.1a or DP 1.4) is
your Graphics Card certied to. Download and
install the latest graphics card driver.
• Some DP 1.1a graphics card cannot support
DP 1.4 monitors. Go to OSD menu, under Input
Source selection, press and hold DP select
Joystick key for 8 seconds to change the
monitor setting from DP 1.4 to DP 1.1a.
No image when
using USB-C
connection
to computer,
laptop, and so
on
(U2722DE only)
Black screen • Verify if the USB-C interface of the device can
support DP alternate mode.
• Verify if the device required more than 90 W
power charging.
• USB-C interface of device cannot support DP
alternate mode.
• Set Windows to Projection mode.
• Ensure that the USB-C cable is not damaged.

6. Trouble Shooting Instructions
Problem What You
Experience
Possible Solutions
No charging
when using
USB-C
connection
to computer,
laptop, and so
on
(U2722DE only)
No charging • Verify if the device can support one of 5 V/9 V/
15 V/20 V charging proles.
• Verify if the Notebook requires a >90 W power
adaptor.
• If the Notebook requires a >90 W power
adaptor, it may not charge with the USB-C
connection.
• Ensure that you use only Dell approved adapter
or the adapter that comes with the product.
• Ensure that the USB-C cable is not damaged.
Intermittent
charging when
using USB-C
connection to
computer,
laptop, and so
on
(U2722DE only)
Intermittent
charging
• Check if the maximum power consumption of
device is over 90 W.
• Ensure that you use only Dell approved adapter
or the adapter that comes with the product.
• Ensure that the USB-C cable is not damaged.
No image when
using USB-C
MST
Black screen or
2nd DUT is not
Prime mode
• USB-C input, Go to OSD menu, under Display
Info check the Link Rate is HBR2 or HBR3, if
Link Rate is HBR2, suggest to use USB-C to DP
cable to turn on MST.
No network
connection
Network
dropped or
Intermittent
• Do not toggle O/On the power button when
network is connected, keeps the power button
On.
The LAN port is
not functioning
(U2722DE only)
OS setting
or cable
connection
issue
• Ensure that the latest BIOS and drivers for your
computer are installed on your computer.
• Ensure that the RealTek Gigabit Ethernet
Controller is installed in the Windows Device
Manager.
• If your BIOS Setup has a LAN/GBE Enabled/
Disabled option, make sure it is set to Enabled.
• Ensure that the Ethernet cable is connected
securely on the monitor and the hub/router/
rewall.
• Check the status LED of the Ethernet cable to
conrm connectivity. Re-connect both ends of
the Ethernet cable if the LED is not lit.
• First power o the Computer and unplug the
Type-C cable and power cord of the monitor.
Then, power on the computer, plug in the
monitor power cord and Type-C cable.

6. Trouble Shooting Instructions
Universal Serial Bus (USB) Specific Problems
Specific
Symptoms
What You
Experience
Possible Solutions
USB interface is
not working
USB peripherals
are not working
• Check that your display is turned ON.
• Reconnect the upstream cable to your
computer.
• Reconnect the USB peripherals (downstream
connector).
• Turn o the monitor and turn it on again.
• Reboot the computer.
• Certain USB devices such as portable hard
drives require higher power source; connect the
drive to the computer directly.
Super speed
USB 3.2 Gen2
interface is
slow.
Super speed
USB 3.2 Gen2
peripherals
working slowly
or not working
at all
• Check that your computer is USB 3.0-capable.
• Some computers have USB 3.0, USB 2.0, and
USB 1.1 ports. Ensure that the correct USB port
is used.
• Reconnect the upstream cable to your
computer.
• Reconnect the USB peripherals (downstream
connector).
• Reboot the computer.
Wireless USB
peripherals stop
working when a
USB 3.0 device
is plugged in
Wireless USB
peripherals
responding
slowly or only
working as
the distance
between itself
and its receiver
decreases
• Increase the distance between the USB 3.0
peripherals and the wireless USB receiver.
• Position your wireless USB receiver as close as
possible to the wireless USB peripherals.
• Use a USB-extender cable to position the
wireless USB receiver as far away as possible
from the USB 3.0 port.
USB is not
working
No USB
functionalities
Refer to input source and USB pairing table.