Dell U2421HE UltraSharp 23.8 inch IPS Monitor User Guide

DELL U2421HE UltraSharp 23.8 inch IPS Monitor

Disassembly Procedures

S1
Open the carton with a proper tool.

S2
Take out all accessories including QSG, Delta-e paper, user’s manual, DP cable, USB cable, power cable and other packing materials from the carton.(Note: It depends on whether users returning the accessories)

S3
Take out the base, stand and Paper-Top from the
carton, then take out the monitor from the pizza carton.

S4
Take out the monitor from EPE-bag and put the LCD monitor on a protective cushion.

S5
Use a Philips-head screwdriver to remove four screws for unlocking mechanisms. (No.1~4 screw size=M4x8; Torque=10~11kgfxcm)

S6
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.


S7
Lift the rear cover up carefully. Disconnect the USB FFC cable from the connector of the interface board, and then remove the rear cove

S8
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)

S9
Tear off 1pcs aluminum foil for unfixing the function key cable

S10
Tear off 2pcs acetate tape for releasing the panel lamp cables. Use a proper tool to release the function key cable from the connector, then pull the function key cable high for releasing the function key cable as the picture below shown.

S11
Use a Philips-head screwdriver to remove screws for unlocking the front bezel with the assembled unit.
(No.1~5 screw size=M2x2.7, Torque=3±0.5kgfxcm)

S12
Use a Philips-head screwdriver to remove  screws(left and right) for unlocking the front bezel with the panel module, then disassemble the front bezel with the unit and put it aside
(No.1~2 Screw size= M3x0.5×4, Torque=3~4kgfxcm)



S13
Tear off the mylar tape on the function key board, then use a Philips-head screwdriver to tighten 3pcs screws for locking the function key board with the front bezel.
(No.1~3 Screw size= M2x2.4, Torque=1±0.2kgfxcm)



S14
Tear off 2pcs acetate tapes for releasing the panel lamp cables, then unplug the panel lamp cables from the connectors of the panel module and power board.

S15
Use a Philips-head screwdriver to remove 4pcs screws for unlocking the bracket chassis module.
(No.1~4 Screw size= M3x0.5×3, Torque=5~6kgfxcm)

S16
Use a Philips-head screwdriver to remove 4pcs screws for unlocking the bracket chassis module.
(No.1~4 Screw size= M3x0.5×3, Torque=5~6kgfxcm)


S17
Turn over the bracket chassis module. Remove the Mylar from the hooks of the bracket, and then use a Philips-head screwdriver to remove screws for unlocking AC power outlet. two
(No.1~2 screw size=M3x10, Torque=6±0.5kgfxcm)


S18
Use a Philips-head screwdriver to remove screws for unlocking power board and interface board. 7pcs
(No.1 screw size=M4x8, Torque=6±0.5kgfxcm; No.2~6 screw size=M3x7.5, Torque=6±0.5kgfxcm)

S19
Remove the circuit boards from the bracket chassis module carefully, and then disconnect all of the cables.

S20
Remove electrolyte capacitors (red mark) from printed circuit boards.

S20-1 Cut the glue between bulk cap. and PCB with a knife.

S20-2 Ensure cutting path within the glue, don’t touch bulk cap. or PCB.

S20-3 Cut into the bottom of bulk cap. and pullet up carefully

S20-4 Take out bulk cap. pin solder with soldering iron and absorber

S20-5 Lift the bulk cap. up and away from the PCB

Product material information

The following substances, preparations, or components should be disposed of or recovered separately from other WEEE in compliance with Article 4 of EU Council Directive 75/442/EEC.

Tools 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