ICT

1. MAINTAINING AND
REPAIRING COMPUTER
SYSTEMS AND NETWORKS
(MRCN)
(RECTIFY/CORRECT DEFECTS IN COMPUTER SYSTEMS AND
NETWORKS)

2. RECTIFY/CORRECT DEFECTS IN COMPUTER
SYSTEMS AND NETWORKS
 Preventive maintenance can be described as maintenance of equipment or
systems before fault occurs. It can be divided into two subgroups: Planned
Maintenance and Conditioned-Based Maintenance. Planned Maintenance
(PM) is any variety of scheduled maintenance to an object or item of
equipment. Specifically, PM is a scheduled service visit carried out by a
competent and suitable agent, to ensure that an item of equipment is
operating correctly to avoid any unscheduled breakdown and downtime of
an equipment.

3. RECTIFY/CORRECT DEFECTS IN COMPUTER
SYSTEMS AND NETWORKS
 Condition Based Maintenance (CBM) is a maintenance strategy that uses
the actual condition of the asset to decide what maintenance needs to be
done. CBM dictates that maintenance should only be performed when
certain indicators show decreasing performance or upcoming failure.
Checking a machine for these indicators may include non-invasive
measurements, visual inspection, performance data and scheduled tests.
Condition data can be gathered at certain intervals, or continuously.

4. RECTIFY/CORRECT DEFECTS IN COMPUTER
SYSTEMS AND NETWORKS
 The purpose of systematic inspection, detection and correction of existing
/ future problems is very important to maintain equipment / facilities in
satisfactory condition before it may cause major problem. Maintenance,
including tests, measurements, adjustments, and parts replacement,
performed specifically to prevent faults from occurring. Maintenance is
divided into two (2) general type.
 Preventive maintenance is given for maintaining equipment and facilities
in satisfactory operating condition to extend the life of the equipment.
Corrective maintenance is task performed to identify, isolate, and rectify a
fault so that the failed equipment or system can be restored to an
operational condition within the tolerances or limits.

5. Maintenance Procedures
 In preparing maintenance procedure, you also must consider designing a
systematic plan for both for hardware and software. This saves time,
money and frustration and ensures safe conditions to prevent injury to
people and damage to computer equipment.

6. Planning Maintenance Procedures for
Computer System and Networking:

7. A. Design a systematic maintenance
plan for hardware.
 1. Design a monitoring, evaluating, and updating
plan.
 2. Place your computer in a well-ventilated area.
 3. Schedule the use of computer for its longer life.
 4. Move the computer only when it is turned off and
unplugged.
 5. Treat your computer properly.

8. B. Design a systematic maintenance plan
for your software.
 1. Backup your files.
 2. Install or secure passwords.
 3. Delete temporary files.
 4. Update anti-virus and spyware

9. Planning Maintenance Procedures for
Computer System and Networking:
 Design a systematic monitoring, evaluating, and updating
plan for hardware. Computers have significantly changed the
working environment, simplifying, and speeding up many
tasks across many work areas. However, with these advances
are some potential problems and maintenance issues. These
guidelines describe how computer technicians, students and
computer users can work together to achieve a productive
workplace environment. The guidelines reflect current
knowledge and best practice for the use of computers so you
can achieve maximum efficiency and safety in your workplace.

10. Planning Maintenance Procedures for
Computer System and Networking:
 Place your computer in a well-ventilated area.
 ❖ This will allow proper circulation of air inside the computer unit.
Schedule the use of computer for its longer life.
 ❖ This will help lessen the attacks of viruses and increases the life span of
your computer. Move the computer only when it is turned off and
unplugged.
 ❖ To avoid damage to the computer unit always turn off and unplug it
when transferring the computer to another location. Treat your computer
properly.
 ❖ This means taking care of your computer. PCs and laptops should be
properly turned off.

11. Do systematic maintenance plan for your computer
software. Back-up your files
 ❖ Protecting your files means creating backups, storing your file backups
on your hard drive or any removable storage device regularly. Install or
secure passwords.
 ❖ Installing passwords makes your files more secure. Delete temporary
files.
 ❖ Deleting the temporary files on your computer will enhance its speed
and will create more disk space for your files. Update anti-virus and spy
ware.
 ❖ Regularly update your anti-virus for your computer protection against
viruses.

12. Preventing Computer Systems Failure
Computers,
 in general, are stable, and you can usually rely
on them to not fail you. However. If you
develop some basic habits, you can postpone
serious computer problems, if not avoiding
them entirely.

13. Preventing Computer Systems Failure
Computers,
 1. Computer issues. Know that your computer is going to fail. You
need to treat your computer as if it were a doomed failure. Always
assume that failure is imminent. A fatal error results in data loss,
damage to your computer and/or its ability to function, hardware
failure, or other serious issues.
 2. Dust issues. Preventing failure means making sure your computer
is physically clean in its operations. Make sure that there is not too
much dust inside, especially on the fans. Dust can reduce
performance and cause overheating.
 3. RAM issues. Know your computer's specifications and its limits.
RAM runs even the PC is running idly. It consumes RAM storages
capacity making you difficult to open a program if RAM storage had
been consumed.

14. Preventing Computer Systems Failure
Computers,
 4. Malware issues. Make sure that your anti-virus software
is updated to be able to scan unnecessary files that enter
your PC. Do not install programs that you’re not familiar
with or if do not fully trust.
 5. Hardware issues. When something is not working
properly, either diagnose the problem yourself and fix it,
to prevent further damage or contact a professional and
have them look at it for you. Take advantage of
warranties on parts if they fail.
 6. Warning issues. If the same error message shows up
every time you log in, be sure to investigate it. Although
unlikely, these errors could be important.

15. Preventing Computer Systems Failure
Computers,
 7. Usage issues. Give your computer a break. Believe it or not, your
computer likes rest, too. Leaving it on all the time wears out hardware and
puts unnecessary wear and tear on the hardware. Giving your computer a
break also saves you money (electrical bills).
 8. Warranty issues. Always take advantage of warranties. Get a warranty to
protect your hardware, so it can be replaced in case of failure.
 9. Backup issues. Back-up everything. Run regular backup of your
important files to other disks, computers, or an online backup service.
 10. Error message issues. If your PC fails to function, diagnose the
problem. Write down the necessary info such as error messages or things
don’t work properly. If you know how to fix it, do it, to avoid further
damage but if not then seek for professional help.

16.  In recent years, software defects have become the
dominant cause of customer outage, and
improvements in software reliability and quality have
not kept pace with those of hardware. Yet, software
defects are not well enough understood to provide a
clear methodology for avoiding or recovering from
them.

17.  Debugging is the group of activities that software developers perform to fix a
bug, so being a good debugger is a very important part of being a good
developer. Three reasons to consider debugging one of your main skills:
 • We spend a lot of time debugging.
 • There are always errors in your code
 • Debugging is sometimes the only way to check that some code is working
fine.
 There are thousands of problems that your PC could have, from an endless list
of possible error messages to various hardware failures. Most of those
problems might have several possible causes as well. Most of these potential
issues are rare. The problems most computer users see are common errors and
failures seen by many, many others

18. There are some of the most common
PC problems:
 • Computer will not turn on
 • Blue screen of death (BSOD)
 • “404” / “page not found” error
 • “Hal.dll is missing” error
 Computers and computer components can fail at any time and for any reason.
If the defect can ultimately be traced back to the design, programming, or
manufacturing process, you might be entitled to recover compensation
through a class-action lawsuit. Many people think that hardware and software
are one in the same. In fact, hardware and software are very different.
Hardware refers to the physical components of the computing unit — tower,
monitor, printer, keyboard, mouse, and the physical pieces of equipment that
comprise these components — while software refers to the coding or built-in
instructions that allow the hardware to run properly.

19. MAINTAINING AND
REPAIRING COMPUTER
SYSTEMS AND NETWORKS
(MRCN)
(INSPECT AND TEST THE COMPUTER SYSTEMS AND NETWORKS)

20. INSPECT AND TEST THE COMPUTER
SYSTEMS AND NETWORKS
 System testing is a series of different tests whose sole
purpose is to exercise the full computer-based
system. System testing falls under the black box
testing category of software testing. White box
testing is the testing of the internal workings or code
of a software application.

21. In contrast, black box or system testing is the opposite. System testing
involves the external workings of the software from the user’s perspective.
System testing involves testing the software code for following:
 • Testing the fully integrated applications including external peripherals to
check how components interact with one another and with the system.
This is also called End to End scenario testing. • Verify thorough testing of
every input in the application to check for desired outputs. • Testing of the
user’s experience with the application.
 That is a very basic description of what is involved in system testing. You
need to build detailed test cases and test suites that test each aspect of
the application as seen from the outside without looking at the actual
source code.

22. Testing Procedure
 ➢ Deciding when to test the system. Identify computer symptoms and
defects.
 ➢ Preparing to test the system. It’s recommended that you should not
plug your computer and monitor directly to a wall outlet. Rather you
should purchase a UPS (Uninterruptible Power Supply). The UPS serves as
a surge protector to prevent your system from being damaged if a power
spike is delivered to it and when power will fail unexpectedly. The UPS
gives you time to save your work and properly shutdown your computer
system. If a system is turned off and back on rapidly, it’s probably not good
for the system. A very short power drop could mimic this effect and could
be hard on both the computer and the monitor. A UPS prevent this.

23. Testing Procedure
 Powering Up the system for the first time. Examining the back of the PC
case we see that there is a switch with two positions, 0 and 1. Zero often
means “Off” and one often means “On” in the computer world. We turn
the switch from 0 to 1 and push the power button again.
 ➢ Adjusting BIOS settings. To enter BIOS setup, a key, such as “Delete” is
usually pressed when the system first starts up. Consult your main board
manual if you want to learn more about BIOS setup.
 ➢ Replacing the side of the case and bezel. Now that your system is tested
and we’ve visually seen that the CPU fan is spinning properly, we can
shutdown the system and replace the side of the case..

24. Computer Symptoms and Diagnosis
 No matter how well built your PC is, and how well written its software,
something is eventually going to go wrong. Many times, computers will
get slow for seemingly no reason at all.
 Devices often malfunction and system problems can arise out of nowhere.
For people who rely on their computer for business or personal use, these
computer errors can be frustrating and problematic. One of the most
important aspects of using a PC is taking care of it.
 Maintenance involves keeping your hard disk in optimum working
condition, checking for errors, and backing up important files.
Maintenance tasks also include adding new hardware to your system and
updating the files that control your hardware (called drivers).

25. ❖ Common Error Messages
 As you work on your computer, there are error messages that come up.
The machine at times tries to tell you where the problem is. These
messages are like detective clues for the Help Desk.
 ❖ Common Problems
 l. My monitor is blacked out
 2. I don't have any sound.
 3. My machine is stuck and won’t do anything

26. ❖ Checking of Peripherals
 Keyboards
 If our machine, when booting, gives off a constant beeping noise, it is telling
that your computer keyboard is not connected or not working. • If there is no
response, check the indicator light on the keyboard. • ls there a key stuck?
Gently pry off the cover and clean it with alcohol. Make sure it is not
connected to your machine when you are cleaning it.
 Mouse •
 If your mouse starts acting erratic, it could be an insufficient memory
problem.
 • If your mouse will only move one way, either vertically or horizontally, your
mouse may need cleaning. Shut down your machine and unplug your mouse
from the computer. • Optical mouse need cleaning of its bottom every now
and then too.

27. ❖ Checking of Peripherals
 Printer
 • Verify that the printer is working correctly by running a test print.
 • Unplug the printer cable from the back of the PC and try to print the printer
 • Reattach the printer and run another test print,
 • Turn off the printer and try to print to it.
 • What error messages appear? Turn the printer back on and run a test print
 • Turn off the printer and remove the ink or toner cartridge. Turn the printer back on. Do
any error messages appear? Try printing to the printer. Do any error messages show up
them?
 • Reinstall the ink or toner cartridge and run a test print. Remove all of the paper from
your printer and then try to print it. What error messages appear now?

28. ❖ Checking of Peripherals
 A Dead PC
 • First check the cable
 • Check the wall outlet
 • Turn the system off and wait for a few seconds and then try again. •
Reach behind the machine and see if you feel air blowing out of the power
supply.
 • Look at the keyboard for the indicator lights being lit up as the machine
boots.
 • Sometimes the monitor has something to do with the system acting up.
Unplug the power cord from the monitor and the wall and re plug it.
 • Listen to identity a beeping series if there is one.

29. Occupational Health and Safety Policy
 In the school as a computer teacher you must be aware of how your
students behave when they are working in the computer laboratory, as
well as implementing a safe way of accomplishing every task. Safety
practices should be learned early find always adhered to when working
with any electrical device, including personal computers and peripherals.
This is for the protection of not only the people working with them, but
also for the devices themselves. The basis for this process begins with your
Occupational Health and Safety Policies

30. Personal Safety While Working Along
with PC’s
 Computer equipment can be dangerous, and you or others can be injured or
even killed if you don't follow proper safety guidelines when working along
PC's. The following are some precautionary measures to take before working
with any computer equipment:
 • Wear shoes with non-conductive rubber soles to help reduce the chance of
being shocked or seriously injured in an electrical accident.
 • Do not work on components that are plugged into their power source.
 • Do not remove expansion cards from a computer when it is turned on.
 • Remove all jewelry when working inside any computer related equipment.
 • Be sure not to mix electronic components and water.

31. The 5S Principles

32. The 5S Principles

33. The 5S Principles

34. The 5S Principles

35. The 5S Principles

36. The 5S Principles

37. The 5S Principles

38. The 5S Principles

39. The 5S Principles

40. The 5S Principles

41. The 5S Principles

42. WEEE Directive (Waste Electrical and
Electronic Equipment Directive)
 The Waste Electrical and Electronic Equipment (WEEE) directive is
legislation that, in conjunction with RoHS, mandates targets for the
collection, recovery and recycling of electronics and component materials.
The WEEE Directive passed in the European Community (EC) in February
2003. One stipulation of the Directive is that manufacturers are
responsible for the disposal of their products and must deal with their
disposal in an environmentally responsible manner. The Directive also
says that the consumer of the goods should be able, at a minimum, to
return them, free of charge, to the manufacturer for disposal. Many
everyday consumer items contain electrical parts. Waste Electrical and
Electronic Equipment (WEEE) is electrical and electronic equipment that is
broken or unwanted. Any appliance that runs on electricity has the
potential to cause damage to the environment if it is not disposed of in a
responsible way.

43. Common items of electrical and
electronic waste are:
 Large household appliances (refrigerators/freezers, washing machines,
dishwashers)
 • Small household appliances (toasters, coffee makers, irons, hairdryers)
1. • Information technology (IT) and telecommunications equipment (personal
computers, telephones, mobile phones, laptops, printers, scanners, photocopiers)
 • Consumer equipment (televisions, stereo equipment, electric toothbrushes)
 • Lighting equipment (fluorescent lamps)
 • Electrical and electronic tools (handheld drills, saws, screwdrivers)
 • Toys, leisure, and sports equipment
 • Medical equipment systems (except for all implanted and infected products)
 • Monitoring and control instruments
 • Automatic dispensers.

44. Install correct components or parts without
damage to the surrounding environment or
services
After completing this lesson, Learners should be able to:
 1. Identify the different installer / components use for
installing
 2. List down the procedure to rectify the computer
systems and networks
 3. Create a step by step in installing the correct
components of computer
 system.

45. L E S S O N
 Install correct components or parts without damage to computers is one
important things to know of ICT students for their future job. In one
mistake can damaged the peripherals that’s the very reason why we should
follow the procedures carefully. How to find the best storage, memory, and
processor to build the best computer possible.
 There has never been a better time to build your own PC, but where’s the
best place to start? Determining what you want to get out of your new
computer is the first step and it guides the rest of the process. When you
know what you want from your computer, you’ll know what you need from
your hardware, which is the source of your computer’s performance. Get
the most performance for less by investing in the right components from
the start. That’s when you can begin to build.

46. The Key Components you’ll need
Once you’ve decided what kind of PC you
want to install, you can begin to research
and purchase the hardware you need to fulfil
your plan. Here are the essential parts:

47. Motherboard
 A motherboard is the first
component you’ll want to
choose. The motherboard
dictates the physical form
factor and size of your PC
build, but it also determines
what other pieces of
hardware the computer can
use.

48. Processor/Central
Processing Unit
(CPU)
 The CPU is the engine of
your computer and sets the
performance expectations for
the entire build. Memory and
storage fuel the processor,
which controls every data
transaction within the PC.
When you’re determining
which CPU to install, pay
attention to the gigahertz
(GHz) – the higher the GHz,
the faster the processor.

49. Memory
 Adding memory (RAM) is one of
the fastest, easiest, and most
affordable ways to amplify the
performance of the computer
you’re building because it gives
your system more available
space to temporarily store data
that’s being used.

50. Storage
 Your files and data are saved
long-term on your storage
drive. This data is held on
either a hard disk drive
(HDD) or solid state drive
(SSD). Although hard drives
generally give you more
storage space (in GB), SSDs
have essentially made them
outdated – SSDs are on
average 6x faster1 and 90x
more energy-efficient2 than
hard drives.

51. Case, fans, and
power supply
 Depending on the kind of PC
you’re building, you’ll also
need to adjust what you’re
looking for with a case and
power supply. If you’re
creating a high-powered
performance workhorse,
you’ll need a robust power
supply to make it all run,
and a case with optimal
internal airflow and fans to
expel hot air that could
potentially damage the
system.