Dell P2722HE User manual

Version: 01
Date: 2021/10/30
Service Manual - P2722HE

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.
Item Description Q'ty Remark
1 1
For EMEA Only, not for
other regions
2
Panel Mylar
1
13
4 1
15
6
USB BD
1
1 7
8 1
9
10
11 1
1
Key BD
12
1 13
1 14
LED BD
Front trim
ASSY Middle Frame
Interface BD
Power BD
1
1
15 1
1
Main bracket
16
Joystick button
See “NOTE”
See “NOTE”
Riser ASSY
Base ASSY
Back cover
Panel
1 17
See “NOTE”
USB Type-C cable(1.8 meter)
Power cable
DisplayPort cable(1.8 meter)
17
16
15

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.
Wedge your fingers between the 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..
Use a Philips-head screwdriver to remove four
screws for unlocking mechanisms.
(No.1~4 screw size=M4x10; Torque=12±0.5kgfxcm)
S3
S2
S1
23
41
1
3
22
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.
S4
S7
Use a Philips-head screwdriver to remove 2pcs
screws for unlocking the joystick key board unit, then
tear off the tapes and release the USB board.
(No.1~2 screw size=M2x3.3,Torque=1±0.2kgfxcm)
S5
12
S6
Use a Philips-head screwdriver to remove one screw
for unlocking the USB board unit, then release the
USB board unit and put it aside.
(No.1 screw size=M3x6, Torque=4±0.5kgfxcm)
Lift the rear cover up carefully. Disconnect the key
cable and USB FFC cable from the connectors of
the interface board, and then remove the rear cover.
Disconnect the panel lamp cable away from the
connectors of the panel module and circuit board,
then release the cable by tearing off tape.
1

5. Disassembly and Assembly Procedures
Take away the
.
middle bezel, and put it on a fixture,
then tear off the mylar tape for releasing the LED
board
S10
S8
S9
S11
S13
S12
Take away the bracket chassis module and then put
the bracket chassis module on a protective cushion.
Put the panel module on a protective cushion, then
push the earing-locks and disconnect the LVDS
cable from the connector of the panel module.
Use a 2pcs
screws for unlocking the bracket with panel module.
Philips-head screwdriver to remove
(No.1~2 screw size=M3x4, Torque=5±0.5kgfxcm)
12
Disconnect the LED cable from the connector of the
board, then tear off 3pcs aluminum foil.
Lift up the panel with the bracket for releasing the
front bezel away from the panel.
Use a Philips-head screwdriver to remove 15pcs
screws for unlocking the middle bezel.
(No.1~13 screw size=M3x4, Torque=5±0.5kgfxcm;
No.14~15 screw size=M1.6x1.7, Torque=1±0.2kgfxcm)
2
10
12 1
11
3
8
13
9
7
45
6
14
15
S14

5. Disassembly and Assembly Procedures
S15 Remove the black Mylar from the hooks of the
bracket as the picture below shown.
Remove the interface board and power board from
the bracket chassis module carefully, and disconnect
all the cables.
Use a Philips-head screwdriver to remove 7pcs
screws for unlocking the power board and interface
board, and then release all the cables from the hooks.
(No.1 screw size=M4x8, Torque=6±0.5kgfxcm;
No.2~7 screw size=M3x7.5, Torque=6±0.5kgfxcm)
2
1
65
4
3
7
S16
S17

5. Disassembly and Assembly Procedures
5.2 Assembly Procedures: Take a mylar to insert the hooks of the bracket to
cover the power board.
S4
Panel preparation: Take a panel and then examine
the panel surface according to inspection criteria.
Tear off the protective film of the panel screen, and
then turn over the panel to place screen faced down.
Paste 1pcs conductive foam on the specific position
as the picture below shown.
S5
Turn over a power board and put the power board
into the correct position of the bracket chassis base
as the picture below shown.
Place a bracket chassis base on a protective
cushion, then paste 2pcs silicon sheet on the
position as the picture below shown.
S2
S1
Take a interface board, connect a LVDS cable to the
connector of the interface board, then connect the
cable of the power board to the connector of the
interface board. Turn over the interface board and
locate it into the bracket. Use a Philips-head
screwdriver to tighten 7pcs screws for locking the
power board and interface board.
(No.1 screw size=M4x8, Torque=6±0.5kgfxcm;
No.2~7 screw size=M3x7.5, Torque=6±0.5kgfxcm)
S3
Put the bracket chassis module on the back of LCD
module, then push the earing-locks and connect
LVDS cable and panel lamp cable to the connectors
of the panel module.
2
1
65
4
3
7
S6

5. Disassembly and Assembly Procedures
Take 1pcs panel lamp cable to connect the panel with
the circuit board, then tear off the tape on the back
the cable and fix the cable as the picture shown.
Take 1pcs LED board and 1pcs middle bezel, then
put the middle bezel into a fixture jip to fix the middle
bezel. Tear off the release paper 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, then fix the cable with
2pcs tapes on the middle bezel by tearing off papers.
Connect the LED cable to the connector of the
interface board, then paste 2pcs aluminum foil to fix
the bracket, then paste 1pcs aluminum foil to cover
the LVDS connector of the panel.
S13
Assemble the middle bezel with the front bezel and
panel module, then adjust the middle bezel for two
parts firmly attachment.
S11
Take a front bezel, then lift up the panel unit and
assemble the front bezel with the panel.
Use a Philips-head screwdriver to tighten 13pcs
screws for locking the middle bezel with the panel.
Use a Philips-head screwdriver to tighten 2pcs
screws for locking the middle bezel with the panel.
(No.1~13 screw size=M3x4, Torque=5±0.5kgfxcm;
No.14~15 screw size=M1.6x1.7, Torque=1±0.2kgfxcm)
S12
2
10
12 1
11
3
8
13
9
7
45
6
14
15
S9
12
Use a 2pcs
screws for locking the bracket with panel module.
Philips-head screwdriver to tighten
(No.1~2 screw size=M3x4, Torque=5±0.5kgfxcm)
S7
S8
S10

5. Disassembly and Assembly Procedures
Use a Philips-head screwdriver to tighten 4pcs
screws for locking rear cover with the assembled
unit. Stick 2pcs labels on the specific positions as
the picture below shown. Insert 1pcs DP cap.
(No.1~4 screw size=M4x10; Torque=12 0.5kgfxcm)±
Move the assembled rear cover close to the
panel unit, then connect the key cable and USB
FFC cable to the connectors of interface 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 USB board and a connect cable. Connect
the cable to the USB board, then paste 1pcs
conductive foam on the back of the board. Locate
the USB board into the hook of the middle bezel.
Use a Philips-head screwdriver to tighten one screw
for locking the USB unit with middle bezel.
(No.1 screw size=M3x6, Torque=4±0.5kgfxcm)
S14
S17
23
41
Take 1pcs assembled stand base, then fit the two
tabs on the upper part of the stand into the grooves
on the back of the monitor, and then press the stand
so that the monitor mounting area snaps onto the
stand.
S18
1
Take 1pcs joystick key, 1pcs joystick board and 1pcs
rear cover, then assemble the joystick key with board.
Locate the joystick board to the correct position of the
rear cover, then use a Philips-head screwdriver to
tighten 2pcs screws for locking the joystick board with
rear cover, then fix the key cable with 2pcs tapes.
(No.1~2 screw size=M2x3.3,Torque=1±0.2kgfxcm)
12
S15

5. Disassembly and Assembly Procedures
L
video signal to the monitor
ift up the monitor, then provide power supply and a
, then turn on the monitor
for functionality check.
S19

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 off both your computer and the monitor.
2. Unplug the video cable from the computer.
3. Turn on the monitor.
If the monitor cannot sense a video signal and is working correctly, the following
message will appear:
or
NOTE: The message may be slightly different according to the
connected input signal.
NOTE: While in self-test mode, the power LED remains white.
4. This box also appears during normal system operation, if the video cable
becomes disconnected or damaged.
5. Turn Off 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
Built-in diagnostics
Your monitor has a built-in diagnostic tool that helps you determine if the screen
abnormality you are experiencing is an inherent problem with your monitor, or with
your computer and video card.
To run the built-in diagnostics:
1. Ensure that the screen is clean (no dust particles on the surface of the
screen).
2. Move and hold the joystick up/down/left/right for about 4 seconds until a
pop-up menu appears.
3. Move the joystick to highlight the Diagnostic icon and then press the
joystick to confirm. A gray test pattern appears.
4. Carefully inspect the screen for abnormalities.
5. Press the joystick to change the test patterns.
6. Repeat steps 4 and 5 to inspect the display in red, green, blue, black, white,
and text screens.
7. Press the joystick to end the diagnostic program.

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
pressed 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 & 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.
Poor Focus Picture is fuzzy,
blurry, or ghosting
• Eliminate video extension cables.
• Reset the monitor to factory settings.
• Change the video resolution to the
correct aspect ratio.
Shaky/Jittery
Video
Wavy picture or
fine movement
• Reset the monitor to factory settings.
• Check environmental factors.
• Relocate the monitor and test in
another room.
Missing Pixels LCD screen has
spots
•CyclepowerOn-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: www.dell.com/
pixelguidelines.

6. Trouble Shooting Instructions
Stuck-on Pixels LCD screen has
bright spots
•CyclepowerOn-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: www.dell.com/
pixelguidelines.
Brightness
Problems
Picture too dim or
too bright
• Reset the monitor to factory settings.
• Adjust brightness & contrast controls
via OSD.
Geometric
Distortion
Screen not
centered correctly
• Reset the monitor to factory settings.
Horizontal/
Vertical Lines
Screen has one or
more lines
• Reset the monitor to factory settings.
• Perform monitor self-test feature
check and determine if these lines are
also in self-test mode.
• Check for bent or broken pins in the
video cable connector.
• Run the built-in diagnostics.
Synchronization
Problems
Screen is
scrambled or
appears torn
• Reset the monitor to factory settings.
• Perform monitor self-test feature
check to determine if the scrambled
screen appears in self-test mode.
• Check for bent or broken pins in the
video cable connector.
• Restart the computer in the safe
mode.
Safety Related
Issues
Visible signs of
smoke or sparks
• Do not perform any troubleshooting
steps.
•ContactDellimmediately.
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.

6. Trouble Shooting Instructions
Missing Color Picture missing • Perform monitor self-test feature
color check.
• 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 different Preset Modes in Color
setting OSD. Adjust R/G/Bvalue in
Custom Color in Color settings
OSD.
•ChangetheInput Color Format to
RGB or YCbCr/YPbPr 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 off 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.