HP 25mx Manual

Maintenance and Service Guide
25mx model
SUMMARY
This guide provides information about spare parts, removal and replacement of parts, diagnostic tests, problem
troubleshooting, and more.

© Copyright 2021 HP Development
Company, L.P.
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owned by its proprietor and used by HP
Inc. under license. NVIDIA is a trademark
and/or registered trademark of NVIDIA
Corporation in the U.S. and other
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registered trademarks of USB
Implementers Forum. DisplayPort and the
DisplayPort logo are trademarks owned
by the Video Electronics Standards
Association (VESA) in the United States
and other countries.
The information contained herein is
subject to change without notice. The
only warranties for HP products and
services are set forth in the express
warranty statements accompanying such
products and services. Nothing herein
should be construed as constituting an
additional warranty. HP shall not be liable
for technical or editorial errors or
omissions contained herein.
First Edition: March 2021
Document Part Number:
L31540- 25mx-MSG-V1
Assembly part number: L31540-001
Product notice
Only trained service personnel familiar with
this product should service it. Before
performing any maintenance or service, be
sure to read “Important Safety Information”.

1
Table of Contents
Getting started ................................................................................................................................................................... 2
Important safety information............................................................................................................................................. 2
RoHS (2002/95/EC) requirements................................................................................................................................... 3
General descriptions.......................................................................................................................................................... 3
Before return to receiver:.................................................................................................................................................. 3
Monitor features ................................................................................................................................................................ 4
Features............................................................................................................................................................................... 4
Front components .............................................................................................................................................................. 5
Rear components............................................................................................................................................................... 6
Locating the serial number and product number........................................................................................................... 7
Illustrated parts catalog ..................................................................................................................................................... 8
How to order parts.............................................................................................................................................................. 9
Removal and replacement procedures ............................................................................................................................ 10
Preparation for disassembly........................................................................................................................................... 10
Power board replacement............................................................................................................................................... 14
Power board- Capacitor repair C707 and C708.......................................................................................................... 15
Main board- Connector repair (Audio, HDMI and DisplayPort)................................................................................. 18
Audio Connector repair- M1.................................................................................................................................... 19
HDMI Connector repair- J2...................................................................................................................................... 20
DP Connector repair- J3........................................................................................................................................... 21
Stick Gasket on the Shielding .................................................................................................................................. 22
Function Test:................................................................................................................................................................... 23
Support and Troubleshooting......................................................................................................................................... 24
Index .................................................................................................................................................................................. 25

2
Getting started
Read this chapter to learn about safety information and where to find additional HP
resources.
Important safety information
It is important to note that this manual contains various CAUTIONS and NOTICES
which should be carefully read in order to minimize the risk of personal injury to service
personnel. Proper service and repair are important to the safe, reliable operation
equipment.
The possibility exists that improper service methods may damage the equipment. It is
also important to understand that these CAUTIONS and NOTICES ARE NOT
EXHAUSTIVE.
The service procedures recommended and described in this service manual with
effective methods of performing service operations. 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.
●Be sure your working environment is dry and clean and meets all government
safety requirements.
●Be sure that other persons are safe while you are servicing the product.
●Do not perform any action that can cause a hazard to the customer or make
the product unsafe.
●Use proper safety devices to ensure your personal safety.
●Always use approved tools and test equipment for servicing.
●Never assume the product’s power is disconnected from the main power
supply. Check that it is disconnected before opening the product’s cabinet.
●Modules containing electrical components are sensitive to electrostatic
discharge (ESD). Follow ESD safety procedures while handling these parts.
●Some products contain more than one battery. Do not disassemble or expose
a battery to high temperatures, such as throwing into fire, or the battery may
explode.
●Refer to government requirements for battery recycling or disposal.
This information provides general service information for the monitor. Adherence
to the procedures and precautions is essential for proper service.
IMPORTANT:
Only trained service personnel who are familiar with this HP Product shall perform
service or maintenance to it. Before performing any maintenance or service, the
engineer MUST read the “Safety Note”.
You must disconnect the power cord from the power source before opening the
monitor to prevent component damage.

3
RoHS (2002/95/EC) requirements
Applied to all countries that require RoHS.
The RoHS (Restriction of Hazardous Substance in Electrical and Electronic
Equipment Directive) is a legal requirement by the EU (European Union) for the global
electronics industry sold in the EU and other countries. Any electrical and electronics
products launched in the market after June 2006 should meet this RoHS requirement.
Products launched in the market before June 2006 are not required to be compliant
with RoHS parts. If the original parts are not RoHS complaint, the replacement parts
can be non-ROHS complaint. If the original parts are RoHS compliant, the
replacement parts MUST be RoHS complaint.
If product service or maintenance requires replacing parts, confirm the RoHS
requirement before replacement.
General descriptions
This manual contains general information. There are two levels of service:
Level 1: Cosmetic/appearance/alignment service
Level 2: Circuit board or standard parts replacement
Before return to receiver:
Please always perform an AC leakage current check on the exposed metallic parts to
be sure the set is safe to operate without damage of electrical shock.
Do not use a line Isolation Transformer during this check.
In case any measurement is out of the limits specified, there is possibility of shock
hazard and the set must be checked and repaired before it is returned to the customer.

4
Monitor features
This chapter provides an overview of the monitor’s features.
Features
Depending on the model, your monitor might include the following features:
●62.2 cm (25-inch) diagonal viewable screen area with 1920 x 1080 resolution,
plus full-screen support for lower resolutions; includes custom scaling for
maximum image size while preserving original aspect ratio
●Anti-Glare panel with an LED backlight
●Wide viewing angle to allow viewing from a sitting or standing position, or when
moving from side to side
●Tilt capability
●Pivot capability to rotate the display head from landscape to portrait mode
●Swivel and height adjustment capabilities
●Removable stand for flexible display head mounting solutions
●DP (DisplayPort) video input
●HDMI (High-Definition Multimedia Interface) video input
●Audio headphone/variable line-out jack
●Plug-and-play capability if supported by your operating system
●Security cable slot provision on rear of monitor for optional security cable
●On-Screen Display (OSD) adjustments in several languages for easy setup
and screen optimization
●HDCP (High-Bandwidth Digital Content Protection) copy protection on all digital
inputs
●Energy saver feature to meet requirements for reduced power consumption
NOTE: For safety and regulatory information, refer to the Product Notices provided in
your documentation kit. To locate updates to the user guide for your product, go to
http://www.hp.com/support to download the latest versions of HP programs and
drivers

5
Front components
To identify the components on the front of the monitor, use this illustration and table.
Table 1-1: Front components and their descriptions
Component
Function
1 Menu button Press to open the OSD menu, select a
menu item from the OSD, or close the
OSD menu.
2-4 Function buttons Use these buttons to navigate through
the OSD menu based on the indicators
next to the buttons that are activated
while the OSD menu is open.
You can reconfigure the function
buttons in the OSD menu to quickly
select the most commonly used
operations.
5 Power button Turns the monitor on or off.
6 Power light
Blue: The monitor is on.
Orange: The monitor is in standby
mode.

6
Rear components
To identify the components on the rear of the monitor, use this illustration and table.
Table 1-2: Rear components and their descriptions
Component
Function
1 Power connector Connects the power cable to monitor
2 Audio-out (headphone) jack Connects headphone to the monitor.
To reduce the risk of personal injury,
adjust the volume before using
headphones, earbuds, or a headset.
For additional safety information, refer
to the Product Notice provided in your
documentation kit.
3 HDMI connector Connects the HDMI cable to the
monitor.
4 DisplayPort connector Connects the DP cable to the monitor.

7
Locating the serial number and product number
The serial number and product number are located on a label on the back of display.
You may need these numbers when contacting HP about the monitor model.
Note: You may need to partially pivot the display head to read the label.

8
Illustrated parts catalog
To identify the monitor major components, use this illustration and table.
Table 2-1: Monitor major components and their descriptions
Item Description Qty
1
ASSY MIDDLE FRAME
1
2 ASSY RC 1
3 ASSY SHD 1
4 ASSY COLUMN 1
5 PCBA IF BD MI 1
6 PCBA SPS BD MI 1
7 PCBA CTRL BD 7
8 PCBA LENS BD 1
9
ASSY BASE
1
10 PANEL 1
5
9
8
7
6
4
3
2
1
10