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MODULE 4:
DIAGNOSE AND
TROUBLESHOOT
COMPUTER SYSTEMS (DT)
Content Standard Performance Standard
The learner demonstrates understanding of the underlying concepts and principles on diagnosing and troubleshooting of computer systems.
The learner independently diagnoses
and troubleshoots computer systems
as prescribed in the TESDA Training
Regulation.
Number of Sessions (Time Allotment): 60 hrs.
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In this module, there will be four (4) major topics that you will
encounter: (1) be plan and prepare diagnosis of computer system errors;
(2) diagnose and configure computer systems and networks; (3) inspect and
test the configured computer systems and networks; and (4) test systems and
networks. The four major topics contains sub-topics which all leads to
diagnose and troubleshoot computer systems. This module contains what
to KNOW, what to PROCESS, what to REFLECT and UNDERSTAND as well
as what to TRANSFER. The competencies for this module are:
LO 1. Plan and prepare for diagnosis of computer systems errors
Follow OHS procedures in planning and preparing diagnosis of computer systems errors
Determine the computer systems errors using manual and software diagnosis
LO 2. Diagnose and configure computer systems and networks
Follow OHS procedures in planning and preparing diagnosis of computer systems and network errors
Identify the diagnosed computer systems and network errors based on the job requirements
Configure computer systems and networks
LO 3. Inspect and test the configured computer systems and networks
Follow OHS procedures in inspecting and testing configured computer systems and networks
Inspect configured computer systems and networks
Replace defective components
Reinstall defective computer systems
Identify network errors
Repair network errors based on standard procedures
Test the configured computer systems and networks
LO 4. Test Systems and Networks
Follow OHS procedures in testing systems and networks
Test computer systems and networks in accordance with the job requirements
Accomplish technical reports on the tests conducted
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In order to master the above listed competencies, you must be
knowledgeable of the topics under what to KNOW, perform activities required
under what to PROCESS, accomplish additional meaningful tasks under what
to REFLECT and UNDERSTAND and finally show some evidences of your
learning by transferring what you have learned in a different context under
what to TRANSFER.
You will be challenged to dig deeper into your prior knowledge and
previous experiences about computer hardware servicing.
Instruction:
Read each of the statements in the left-hand column of the chart.
Place a check on the column that indicates your answers.
Knowledgeable Have a Little
Knowledge
No Knowledge
at All
Plan and prepare work to ensure occupational health and safety (OHS) policies and procedures are followed
Obtain materials, tools, equipment and testing devices needed to conform with job requirements
Interpret work instructions according to job requirements
Obtain computer components/devices/systems and determines its location prior to installation
Install equipment/devices/systems in accordance with job requirements
Check/Test devices/systems and/or installations to determine the conformity to job requirements.
Check computer systems and networks for configuration in accordance with specifications
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and requirements
Diagnose fault or problem in the computer systems and networks in line with standard operating procedures (SOP)
Configure the identified systems and networks based on specifications and job requirements
Inspect and test configured computer systems and networks in conformity with manufacturer's instructions/manual
Correct/adjust components or parts of computer systems and networks in accordance with job requirements
Test computer systems and networks to ensure safe operation
Perform scheduled/periodic maintenance in accordance with manufacturer's requirements
Make needed repairs/replacements in accordance with established procedures, when necessary
Document tasks undertaken in accordance with SOP
Clean and clear worksite of all surplus/excess materials in accordance with company SOP
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LESSON 1: PLAN AND PREPARE FOR DIAGNOSIS OF COMPUTER
SYSTEMS ERRORS
SAFETY PRECAUTIONS
Personal Protective Equipment
Proper preparation is the key to a successful work. Before you begin,
make sure that you have the tools you will need, and secure a clear well-lit
workplace. Gather all
same time. Always keep in mind that personal protection is one of the traits of
a good computer technician.
Types of personal protective devices
1. Anti-static devices
2. Power surge protectors
3. Personal equipment
Anti-static devices
Devices designed to protect the computer from static electricity.
Source: www.desktopreality.com
Anti-static Wrist Strap
Source: www.desktopreality.com
Anti-static Mat
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Source: www.desktopreality.com
Anti-static Bag
Source: www.rapidonline.com
Anti-static Spray
Power surge protectors
Devices designed to protect the computer from sudden power surges
from intermittent power sources.
Examples:
1. AVR (Automatic Voltage Regulator)
Source: www.neopower.com
2. UPS (Uninterrupted Power Supply)
Source: www.amazon.co.uk
http://www.neopower.com/http://www.amazon.co/171
Personal Equipment
small paint brush
screw drivers
pliers and tweezers
compressed air
handheld vacuum
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Directions: Perform the activity below.
Choose a partner
Do a simulation exercise
o One will act out the role of a computer teacher.
o The other will be the student
Situation: Computer teacher will show/demonstrate to the students the
Personal Protective Devices, what they are and how they are used.
The Student keeps on asking about the Personal Protective
Devices/Equipment and how they can be maintained in good condition
of PC.
Answer the following questions in your own answer/test notebook.
1. What personal protective devices do people who always works (do
troubleshooting) with computers commonly use? How often do they
use them?
2. Computers should be protected from static electricity to prevent
component malfunction. What anti-static devices can you utilize to
avoid such malfunction?
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TYPES OF COMPUTER SYSTEM ERROR
There are several errors in a computer from the point you open it upto the
point you reach the stand by window (reaching standby windows means boot
process has no error). Below is a list of computer errors.
1. No Video Output - When you open your PC, nothing shows up in your
monitor and the LED indicator of your monitor is flashing in yellow color.
2. No Video Output - Same as number one but now the LED indicator of your
monitor is in steady orange color.
3. Doesn't Boot - When you open your PC it will show the processor brand
and/or the motherboard brand but doesn't continue. Usually this error will
result to system restart over and over again.
4. Never Ending Loading of Operating system - The computer opens up then
boots but when the operating system loads it, doesn't continue and it will take
a longtime if you're going to wait for it to load.
5. Lots of pop up windows showing on standby mode - This also happens
even if you try disconnecting your computer set from the internet. This is what
we called aftershock virus which will continue to run even if internet is
disconnected.
6. Lots of hardware installation windows appear - This happens even if you try
installing the hardware. When you restart your set it will happen again.
7. Safe mode doesn't work - When you try going to safe mode, all you will see
is a list of files in Command prompt style.
8. Keyboard and mouse system restart - This will happen only in standby
mode, when you move your mouse or type something, your system will
automatically restart and the worst part is it will delete a file at random.
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9. Sound on/off error - Upon loading the operating system, you will hear a
loading sound and then the sound stops, when you try running an audio file,
no sound will be heard.
10. Application causes system to restart - Just like the mouse problem, when
you open a program that will take the whole screen like for example a game
and/or a program applications, when you close it, it will cause your system to
restart.
Aside from the common computer errors, computers also can have
different Operating System (OS) errors. OS errors can be classified into
various categories such as:
1. System errors These are moderately dangerous types of errors
among those that can pop up on your PC. System errors are caused
by malfunctioning hardware components, corrupted operating system
modules, etc.
2. Runtime errors Runtime errors are caused by corrupted or
malfunctioning system files or software executables. Most runtime
errors cause the application that caused it to shut down. However,
more serious runtime errors may cause the system to become
unstable or unresponsive, suggesting that you should restart your
computer.
3. Stop errors Stop errors are caused by corrupted hardware,
especially malfunctioning RAM modules and bad sectors on hard
disks. Stop errors can be difficult to resolve at times.
4. Device Manager Errors These are usually caused by corrupted
driver files or malfunctioning hardware components. In case of the
former cause, the problem is often solved by reinstalling or updating
the drivers. However, the latter cause can often be solved only by
replacing hardware components.
5. POST code errors POST code errors are caused by malfunctioning
hardware components, and are characterized by short beep sounds
from the tiny internal speaker of your motherboard. POST code errors
occur when you press the power button to turn on your PC.
6. Application errors These can happen at any point of time. As the
name suggests, these are caused by applications while those are
running. These are commonly caused by glitches in the program code
itself. These are normally resolved by updating the program to its latest
version.
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7. Browser Status Codes These are caused by problems faced by
browsers when trying to access a website. These can be caused by
misplaced web pages in the server of the website itself, or due to
connection problems. For instance, a 404 error would indicate that the
browser is trying to access a webpage that does not exist in the
specified location.
DIAGNOSING COMPUTER SYSTEMS
PC Diagnosing
Probably the most frustrating problem computer users
run into are startup problems, where your computer
you
process. In this module, you will be given a few tips on
how you can avoid some of the most common problems
that happen right after your computer is turned on. Here
you will learn the basic troubleshooting.
Trial and error: When you find a faulty component in your computer,
check it with the other computers so that you can make sure whether
the fault is in the component or not.
Check cables: In case of any device failure, check all the cables of
your computer such as data cables, power cable, internal circuitry
cable and make sure that all these are plugged in and working fine.
Hardware settings: Check the hardware settings in the CMOS and in
the device manager of the system and make all the device drivers up
to date and all the cards are plugged in properly.
Notice changes: When you notice a software or hardware error in
your computer, determine what was changed before the problem
occurred.
Event viewer: In the event viewer, you will find the error or warning
messages associated with any faulty hardware or software.
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Make notes: Troubleshooting is a useful skill and we can learn a lot
when we face any kind of troubleshooting in our computer. Make notes
including the error messages and their solutions, so that you have a
record on how a certain problem occurred and how did you solve it.
Common PC Problems and Solutions
You are working away at your computer when suddenly, an error
message or worse, your computer comes to a screeching halt. Here are the
common computer problems and solutions that can help you.
Steps
1. Check the POST. POST stands for Power On Self-Test. This is generally
the first or second thing that appears on a computer after turning on the
power. This appears before the operating system begins to load. The POST
will display any problem found with the hardware that makes the computer
unable to boot. POST may also display problems with hardware that allow the
computer to boot, but not operate at its full capacity during operation.
2. Notice the load time of the OS (operating system). A longer than usual
load time may indicate errors in the hard drive.
3. Notice any graphics problems once the OS has loaded. Reduced
graphics may indicate driver failures or hardware failures with graphic cards.
4. Perform an auditory test. An auditory test is a simple, but still effective
way of judging how a computer is working. With the computer on and running,
play any decent length audio file (usually above 30 sec.) If the audio is
choppy or slow, it usually means that the processor is working at an elevated
level, or there is not enough RAM to run all programs loading. Changing the
startup sound is a great way to apply this test. Another issue associated with
choppy sounds is PIO (Programmed Input/Output) Mode. This affects how the
hard drive reads and writes data from a drive. Switching to Direct Memory
Access (DMA) allows for faster reads and writes, and can sometimes repair
choppy audio.
5. Check any newly installed hardware. Many operating systems,
especially Windows, can have conflicts with new drivers. The driver may be
badly written, or it may conflict with another process. Windows will usually
notify you about devices that can cause or have any problem. To check this
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use the Device Manager, this can be accessed by entering the Control Panel,
clicking the System icon, clicking the Hardware tab, and clicking on Device
Manager. Use this to check and arrange the properties of hardware.
6. Check any newly installed software. Software may require more
resources than the system can provide. Chances are that if a problem begins
after software starts, the software is causing it. If the problem appears directly
upon startup, it may be caused by software that starts automatically on boot.
7. Check RAM and CPU consumption. A common problem is a choppy or
sluggish system. If a system is choppy it is good practice to see if a program
is consuming more resources than the computer can provide. An easy way to
check this is to use the Task Manager, right click on the taskbar select Task
Manager, and click the Processes tab. The CPU column contains a number
that indicates the percentage of CPU the process is consuming. The Memory
Usage column indicates how much memory a process is consuming.
8. Listen to the computer, if the hard drive is scratching or making loud
noises, shut off the computer and have a professional diagnose the
hard drive. Listen to the CPU fan, this comes on a high speed when the CPU
is working hard, and can tell you when the computer is working beyond its
capacity.
9. Run a virus and malware scan. Performance problems can be caused by
malware on the computer. Running a virus scan can find any problem. Use a
commonly updated virus scanner (such as Norton Antivirus or Avast!
Antivirus)
10. Check for the problem in safe mode. To enter safe mode, press F8
repeatedly during POST (this works on most systems). If the problem persists
in safe mode, it is a fair bet that the operating system itself is to blame.
Common Trouble shooting for Computer Units
1. Double check the power connections.
2. Voltage regulator and power supply could cause power failure in the
computer unit.
3. Check the power cords and cable connectors in your computer unit.
4. Unseated card. Loose cards could cause malfunction.
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5. Check the boot sequence configuration in the advance BIOS (Basic
Input/Output Unit) setup.
Diagnosing Network Connection
Things to look for if a PC is connected to the internet or network:
First, check the cable connecting to the network card into the network
hub.
Check the back of the computer to see if the network card light is on
Check the network cable (use cable tester)
Check the network hub (use multi-tester)
Identify the following:
1. Moderately dangerous types of errors that can pop up on your PC.
2. Caused by malfunctioning hardware components and characterized by
short beep sounds from the tiny internal speaker of your motherboard.
3. They happen at any point of time. As the name suggests, these are
caused by applications while those are running.
4. Usually caused by corrupted driver files or malfunctioning hardware
components.
5. Caused by corrupted or malfunctioning system files or software
executables.
6. Caused by corrupted hardware, especially malfunctioning RAM
modules and bad sectors on hard disks.
7. Caused by problems faced by browsers when trying to access a
website.
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Task: Develop a Sample Diagnostic Plan
List down all possible components to be checked based on the symptoms.
Symptoms: Dead Computer Monitor
Good Defective Remedy
AC outlet
AVR
AVR fuse
Monitor Power Cable
Monitor Switch
Power Supply
Diagnosing a Computer Power Supply
Create a diagnostic plan for troubleshooting a power supply with the
use of the following tools, materials and equipment.
You will be assessed using the following criteria:
CRITERIA Passed Failed
1. Sequence of steps in diagnosing is followed.
2. Safety precaution is observed.
3. Appropriate tools are used in diagnosing.
4. Diagnostic plan for troubleshooting is created.
PERFORMANCE RATING
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LESSON2: DIAGNOSE AND CONFIGURE COMPUTER SYSTEMS AND
NETWORKS
SAFETY PRECAUTIONS
Occupational Health and Safety (OHS) refers to the legislation,
policies, procedures and activities that aim to protect the health, safety and
welfare of all people at the workplace.
Every worker has the right to a healthy and safe work and to a work
environment that enables them to live a socially and economically productive
life. Safety practices should be learned early and must be followed when
working with any electrical device including personal computers and
peripherals.
The following are some safety precautions to take before working with any
computer devices:
uction to prevent
accidents or any unwanted events that may occur on your workplace.
Do not work on a computer when you are wet because you might get
electrocuted.
Do not remove internal devices of the computer when it is turned on.
Avoid playing or running while inside the room.
Always wear personal protective equipments (PPE) like coverall, shoes
with rubber sole, anti-static wrist strap, etc.
Ask for assistance from your teacher when it comes dealing with
computer devices.
Applying safety measures when handling tools and equipment are
necessary to avoid certain damages.
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The student is further expected to maintain good health, to be neat in
personal appearance and to practice safe working procedures at all time with
appropriate equipment.
Basic Concepts of Electricity
This lesson will introduce you to the fundamental knowledge of
electricity. It will equip the student with the basic knowledge in electricity.
Basic Electrical Terms
Electricity Is defined as the flow of electron or electric current. It
is an invisible form of energy that can be
transformed into other forms of energy like heat light
and mechanical.
Electron Is the negatively charged component of an atom. It
has the ability to flow.
Proton Is the positively charged component of an atom. It
has the ability to attract electron.
Matter Is anything that occupy space and has mass. It can
be a solid, liquid or gas in state.
Atom Basic component of matter. It composes of a
nucleus which is the central part, the protons and
electrons.
Current Same as electricity or flow of electron. The amount
of current flowing in a circuit can be measured in
ampere (I).
Voltage The amount of pulling force that makes the electron
flow. Also known as potential difference or EMF
(electromotive force). The amount of voltage can be
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measured in volt (V).
Resistance Defined as the opposition to the flow of current. The
Conductors and Insulators
Conductors are materials that easily allow the flow of current, or it has
a low resistance to current flow.
Examples; aluminum, gold, silver, copper, iron
Insulators are materials that do not easily allow the flow of current, or
it has a high resistance to current flow.
Examples; rubber, plastic, paper
Types of Current
1. Direct Current
In direct current (DC), the flow of electric charge is only in one
direction, the type of electricity produced by batteries, static, and lightning.A
voltage is created and maybe stored until it is consumed when the current
flows directly, in one direction. In the circuit, the current flows at a specific,
constant voltage (this is oversimplified somewhat but good enough for our
needs.) When you use a flashlight, pocket radio, portable CD player or
virtually any other type of portable or battery-powered device, you are using
direct current.
Most DC circuits are relatively low in voltage; for example, your car's
battery is approximately 12V, and that's about as high a DC voltage as most
people ever use.
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Source: www.electrostudy.com
Figure 1.Direct Current
Figure 1 shows an ideal 12 V DC current. The voltage is considered
positive because its potential is measured relative to ground or the zero-
potential default state of the earth.
Direct currents flow in one direction only and are constant in time. Their
appearance is that of a straight line which does not vary. They are produced
from power sources such as batteries, power supplies and DC generators.
Photovoltaic devices such as solar cells also generate DC power.
2. AC Alternating Current
In alternating current (AC, also ac) the movement of electric charge
periodically reverses direction. This type of electricity is produced or
generated by AC generators commonly from a hydro electric plant. It is the
commercial power that we use in homes and offices. Delivered through a
power transmission lines.AC current can be reduced through the use of
power transformer to suite for its application.It can also be converted to DC
for a specific purpose. In the Philippines AC is rated as 220V AC at 60 Hz.
Alternating currents change direction, flowing first one way and then
the other. They are sinusoidal waves, so that they change in time. They are
produced from sources such as power supplies and AC generators. In North
America, AC is 120 volts and 60 hertz or cycles per second. This means it
changes direction 60 times per second. In Europe, it is generally 50 hertz with
220 to 240 volts.
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Source: www.electrostudy.com
Figure2. Alternating Current
Why does standard electricity come only in the form of alternating
current?
There are a number of reasons, but one of the most important is that a
characteristic of AC is that it is relatively easy to change voltages from one
level to another using a transformer, while transformers do not work for DC.
This capability allows the companies that generate and distribute electricity to
do it in a more efficient manner, by transmitting it at high voltage for long
lengths, which reduces energy loss due to the resistance in the transmission
wires. Another reason is that it may be easier to mechanically generate
alternating current electricity than direct current.
provided by your utility must be converted to direct current before use.
This is the primary function of your power supply.
Figure 3.Simplified block diagram of a PC power supply
AC POWER
PC PSU DC POWER
MOTHERBOARD
DRIVES
COOLING FANS
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Electric Circuit
Electric circuit - is the pathways for electricity to flow.
Components of Circuit
Load - commonly represented by a bulb or any electrical component
that consumes electricity.
Supply - Commonly represented by a cell or a battery
Switch - an electrical device that opens or closed a circuit.
Figure4. A simple circuit
Types of Circuit
1. Open Circuit - a type of circuit that has an open path for current to flow. It
means that current cannot flow in open circuit.
Figure5. An open circuit
Load
Switch
Supply
- +
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2. Closed Circuit - a type of circuit that has a closed path for current to flow.
It means that current can flow in a closed circuit.
Figure6. A closed circuit
I. Identification:
Direction: Identify the following statement.
_________1. Defined as the flow of electron or electric current. It is an invisible
form of energy that can be transformed into other form of energy
like heat light and mechanical.
_________2. The negatively charge component of an atom. It has the ability to
flow.
_________3. Defined as the opposition to the flow of current. The amount of
resistance can be measured
_________4. The positively charged component of an atom. It has the ability to
attract electron.
Load
Switch
Supply
- +
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_________5. Anything that occupy space and has mass. It can be a solid, liquid
or gas in state.
_________6. Basic component of matter. It is composed of a nucleus which is
the central part, the protons and electrons.
_________7. Same as electricity or flow of electron. The amount of current
flowing in a circuit can be measured in ampere (I).
_________8. The amount of pulling force that makes the electron flow. Also
known as potential difference or EMF (electromotive force). The
amount of voltage can be measured in volt (V).
_________9. Materials that easily allow the flow of current, or it has a low
resistance to current flow.
_________10. Materials that do not easily allow the flow of current, or it has a high
resistance to current flow.
_________11. A computer power supply converts AC to ___________________.
_________12. Define as the pathways for electricity to flow.
_________13. A component of a circuit that is commonly represented by a bulb or
any electrical component that consumes electricity.
_________14. A component of a circuit that is commonly represented by a cell or
a battery.
_________15. An electrical device that opens or closed a circuit.
_________16. A type of circuit that has a closed path for current to flow. It means
that current can flow in this circuit.
_________17. A type of circuit that has an open path for current to flow. It means
that current cannot flow in this circuit.
_________18. A circuit connection has only one path of current flow. In this circuit
connection the current remain constant.
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_________19. A circuit connection that has 2 or more path of current. In this circuit
the voltage remains constant.
_________20. An invisible form of energy.
Techniques for diagnosing computer systems
Computer Diagnosis
Sometimes when the problem with a system is not totally apparent and
intermittent, using a basic common diagnostic procedure may help determine
what is wrong. This procedure has a number of steps that, if followed each
time, can be of help.
Rules in Diagnosing Computer System
1. Know the facts
Educate one self on all aspects and operation of computer parts.
Continuous learning on computer technology. 2. Use your common sense 3. Focus on Field Replaceable Units
Identify the different types of FRU that can be used for replacement or subassembly.
4. Proper assembly and disassembly 5. Factors Causing Computer Failures and Defects
Peopleware
Untrained personnel could have damaged programs in PC.
Firmware
Programs or software burnt in chips may be corrupted.
Software
Corrupted operating systems would cause the system to fail.
Hardware
Defective hardware components would lead to computer malfunction. Hardware conflicts and viruses can hinder your computers performance.
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ESD (Electro Static Discharge)
Electro static discharge can easily damage sensitive components in yourcomputer. Electricity
Incoming supply from AC outlet must be regulated; power surges can
damage computer units.
Problem Isolation
Problem isolation is a detective work in which you need to determine
what is out of the ordinary by making detailed observation of what is not
working normally and record any information as you proceed. The information
you will be able to gather will help diagnose your computer. You need to
observe wisely. Look for any abnormalities in the unit, any change in smell or
foreign smell, listen to all the sounds, and error codes.
Component Isolation
This section will aid in determining components in your system which
are failing. First, most systems have 3 major components; monitor, system
unit, and printers. Some have multiple external devices. To troubleshoot, you
need to isolate major components which are failing to operate.
Diagnostics Procedure for ATX Power Supply Failure
1. Determine whether or not the power comes on.
2. Check the switch operation with a Digital Volt Meter on the
continuity or resistance setting.
3. Check the pins if the corresponding voltage are properly
regulated to the motherboard.
4. Replace the power supply unit if defective.
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Flowchart for ATX Power Supply Repair
Warning! You must unplug your ATX power supply from the wall before working inside the case.
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Things to Consider:
There are many devices, parts, cords, and connections on a computer,
which means that there are many possible problems that could arise. In
addition, your computer uses a variety of software, which can also cause
problems. However, no matter what the problem is, you can use the
following tips to help you find a solution:
Always check the cables: Many computer problems are related to an
issue in the cables and connections. The easiest first step you can take to
troubleshoot most problems is to check all related cables and connections.
Isolate the problem: If possible, try to isolate the problem. For example, if
you can't get the cursor to move on the screen, try to determine if the
issue is with the mouse. If you have an extra mouse, you can alternate
devices to see if the one plugged in is the issue, or use the arrow keys on
the keyboard to help determine if the mouse is the source of the problem.
When trying to isolate the problem, only make one change at a time.
Figure 7. An error message
Take notes about error messages: If your computer gives you error
messages, be sure to write down as much information as possible. If the
basic troubleshooting steps don't work, you may need the information you
have taken.
Remember the steps you've taken, or write them down: Once you start
troubleshooting, you will want to remember what you have done, so you
don't repeat yourself. If you can't remember it, then write it down. If you
end up asking someone for help, it will be much easier if they know
exactly which steps you've taken.
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Simple Solutions to Common Problems
Most of the time, problems can be fixed by using simple
troubleshooting techniques, such as closing and re-opening the program.
It's important to try these simple solutions before resorting to more extreme
measures. If the problem still isn't fixed, you can then try other
troubleshooting techniques, such as reinstalling the software.
Program Runs Slowly or Isn't Working Right
If a program is running slowly or otherwise isn't working right, the first thing
you should try is closing the program and re-opening it.
You can also shut down your computer, wait a few seconds, and boot it
up again. Some minor problems will work themselves out when you do
this.
Check with the company for any known problems or updates to the
software.
Figure 8.Checking for updates
Program is Completely Unresponsive
If a program has become completely unresponsive, you can press (and
hold) Control+Alt+Delete on your keyboard to open the Task Manager.
You can then select the program that isn't working and click End Task. If
you are using a Mac, you can press Option+Command+Esc to open a
similar dialog box.
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Figure 9.The Task Manager
Problems Starting or Shutting Down the Computer
Figure 10.Resetting a surge protector
If your computer does not start, begin by checking the power cord to
confirm that it is plugged securely into the back of the computer case and
the power outlet.
If it is plugged into an outlet, make sure it is a working outlet. Often, this
will require you to plug a lamp or other electrical device into the outlet to
make sure it is receiving power.
If the computer is plugged into a surge protector, verify that it is turned
on. You may have to reset the surge protector by turning it off and then
back on. You can also plug a lamp or other device into the surge protector
to verify that it is on.
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If you are using a laptop, the battery may not be charged. Plug the AC
adapter into the wall and then try to turn on the laptop. If it still doesn't
start up, you may need to wait a few minutes and then try again.
"Non-System Disk or Disk Error" Message
If you get this message when you boot up your computer, it usually
means there is a CD, DVD, USB flash drive, or floppy disk in your
computer, which is interfering with your computer's booting process.
Remove the disk from the drive and restart the computer.
Figure 11.The Non-System Disk or Disk Error Message
Windows Shutting Down Message Will Not Disappear
Sometimes Windows will freeze during the shutdown process. If
this happens, the Windows is Shutting Down message screen will stay
active on your screen. To finish shutting down the computer, press and
hold the power button for about 10 seconds, or until the computer turns
off.
Figure12.The Windows shutdown screen
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Computer Begins Randomly Rebooting or Crashing
Check for overheating. Make sure the vents in the case are not blocked.
Confirm that there is good air flow around the computer.
Update your antivirus software and scan for viruses.
Figure13.Virus Scanning
Problems with the Monitor and Speakers
No Picture on the Monitor
Confirm the computer is turned on.
Check the brightness control, located on your monitor or your keyboard,
and make sure it is not set too low.
Check the connections for the monitor and surge protector, and make
sure the surge protector is turned on.
Figure 14.Cable plugged into monitor
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Monitor Goes Blank Periodically
You may have the screensaver
enabled. If the screen saver is
enabled, just move your mouse
back and forth and your original
screen will appear. You can
change the screensaver settings
by going to your Control Panel
(or your System Preferences if
you're using a Mac).
Figure 15.Opening the Control Panel
No Sound
Figure 16.Adjusting the sound volume on a Mac
Check the volume control on your computer. In Windows, the sound icon
will usually be on the taskbar, and you can also access the sound options
in the Control Panel. On Macs, the sound options are found at the top of
the screen or in System Preferences.
Most media programs (such as iTunes or Windows Media Player) have
a volume control, which will need to be turned up.
Make sure the speakers are turned on, if using external speakers.
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Make sure external speakers are connected to the correct audio port or a
USB port. If your computer has color-coded ports, the audio output will
usually be green.
Connect headphones to the correct audio port and determine if sound is
audible from the headphones.
Searching the web for a solution
If you still haven't found a solution to your problem, you may need to
ask someone else for help. Try searching the web for the problem that
you're having, as other people may have had similar problems. Also, if you
have a friend or family member who knows a lot about computers, they may
be able to help you.
Keep in mind that most computer problems have simple solutions,
although it may take some time to find them. For very difficult problems, a
more drastic solution may be required, such as reformatting your hard
drive, reinstalling programs, or reinstalling your operating system. If you're not
a computer expert, it's possible that you could make the situation worse, so
it's best to consult a professional if you think a drastic solution is needed.
Task. Examining the Motherboard in Detail
1. Look at the back of your computer. Without opening the case, list the ports
that you believe come directly from the motherboard.
2. Remove the cover of the case. List the different expansion cards in the
expansion slots. Was your guess correct about which ports come from the
motherboard?
3. To expose the motherboard so you can identify its parts, remove all the
expansion cards.
4. Draw a diagram of the motherboard and label these parts: Processor
(Include the prominent label on the processor housing.)
a) RAM (each DIMM slot)
b) CMOS battery
c) Expansion slots (Identify the slots as PCI, PCIe x1, PCIe x4, PCIe
x16, and AGP.) Each port coming directly from the motherboard
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Power supply connections, SATA or IDE drive connectors and
floppy drive connector
5. Draw a rectangle on the diagram to represent each bank of jumpers on
the board.
6. What is the brand and model of the motherboard?
7.
manual on the site, download it.
8. You can complete the following activity only if you have the documentation
for the motherboard:.
What do you do if a program on a PC is completely unresponsive? What
about a program on a Mac?
What should you do if you've tried everything and the problem still isn't
fixed?
Diagnosing Power Supply Failure
Directions: Divide the class into five (5) groups. Choose a leader for each
group. The group will prepares a chart and perform the tasks required by the
Diagnostics Procedure of ATX Power Supply Failure. After the activity
they will be graded through the given Performance Score Card below:
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PERFORMANCE SCORE CARD
Performance Criteria Passed Failed
1. The students clearly identified the problem and applied
the possible solution correctly.
2. The students utilized actual tools/device in performing
the actual usage of each tools and OHS was observed.
3. The students applied safety precautions during the
Activity.
4. The activity gave students more critical thinking on the
personal protective equipment.
5. The students cooperatively performed the activity.
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Tools for Testing Computer System
Tools and equipment play vital roles in troubleshooting. They help the
user determine the errors found in their computer hardware and network.
Tools used to test hardware problems:
1. Screw drivers - are used for installing and removing screws in the computer
unit.
Figure 17.Screw Drivers
2. Pliers and tweezers - are used for picking small parts in the computer unit.
Figure18. Pliers and Tweezers
3. Soldering iron- is primarily used for connecting terminals in the power supply and circuit board with the use of a soldering lead.
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Figure19. Soldering iron
4. Anti-static wrist strap, mat and spray- are used for eliminating electrostatic
discharge in the work area.
Figure20. Anti- static wrist strap, mat and spray
5. Lens cleaner a device used for cleaning optical media, such as DVD-
ROMS and CD-writers.
Figure21. Lens Cleaner
6. Thermal paste-is a paste used for heat dissipation of the processor.
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Figure22. Thermal Paste
Network Troubleshooting Tools
1. LAN Tester is a device used for testing the network connection.
Source: www.nudata.com
Figure23. LAN Tester
2. Crimping tool- is a device used to crimp the RJ45 connector to the UTP
cable.
Source: www.ted-kyte.com
Figure24. Crimping Tool
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Direction: Answer the following question. Write your answers on your
notebook.
.
Enumerate the six tools used for
troubleshooting.
1.
2.
3.
4.
5.
6.
2. Enumerate the two
network troubleshooting
tools.
a.
b.
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Troubleshooting computer system network
Causes of Network Trouble
If a computer is unable to connect to a network or see other computers
on a network, it may be necessary to troubleshoot the network. A network
may not work because of any of the reasons below.
1. Network card not properly connected.
2. Bad network card drivers or software settings.
3. Firewall preventing computers from seeing each other.
4. Connection related issues.
5. Bad network hardware.
Solution
Because of the large variety of network configurations, operating
systems and setup, not all of the below information may apply to your network
or operating system. If your computer is connected to a company or large
network, or you are not the administrator of the network, it is recommended
that if you are unable to resolve your issues after following the below
recommendations, you should contact the network administrator or company
representative.
Verify connections / LEDs
Verify that the network cable is properly connected to the back of the
computer. In addition, when checking the connection of the network cable,
ensure that the LEDs on the network are properly illuminated. For example, a
network card with a solid green LED or light usually indicates that the card is
either connected or receiving a signal.
If, however, the card does not have any lights or has orange or red
lights, it is possible that the card is bad, not connected properly, or the card is
not receiving a signal from the network.
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If you are on a small or local network and have the capability of
checking a hub or switch, verify that the cables are properly connected and
that the hub or switch has power.
Adapter resources
Ensure that if this is a new network card being installed into the
computer that the card's resources are properly set and not conflicting with
any hardware in the computer.
Adapter functionality
Verify that the network card is capable of detecting or seeing itself by
using the ping command. Windows / MS-DOS users ping the computer from a
MS-DOS prompt. Unix / Linux variant users ping the computer from the shell.
To ping the card or the local host, type either ping 127.0.0.1 or ping
local host
This should show a listing of replies from the network card. If you
receive an error or if the transmission failed, it is likely that either the network
card is not physically installed into the computer correctly, or that the card is
bad.
Protocol
Verify that the correct protocols are installed on the computer. Most
networks today will utilize TCP/IP, but may also utilize or
require IPX/SPX and NetBEUI.
When the TCP/IP protocol is installed, unless a DNS server or other
computer assigns the IPX address, the user must specify an IP address as
well as a Subnet Mask. To do this, follow the instructions below.
1. Click Start / Settings / Control Panel
2. Double-click the Network icon
3. Within the configuration tab double-click the TCP/IP protocol icon. Note: Do
not click on the PPP or Dial-Up adapter, click on the network card adapter.
4. In the TCP/IP properties click the IP address tab
5. Select the option to specify an IP address
6. Enter the IP address and Subnet Mask address, an example of such an
address could be:
IP Address: 102.55.92.1
Subnet Mask: 255.255.255.192
http://www.computerhope.com/jargon/t/tcpip.htmhttp://www.computerhope.com/jargon/i/ipxspx.htmhttp://www.computerhope.com/jargon/n/netbeui.htmhttp://www.computerhope.com/jargon/s/subnetma.htm206
7. When specifying these values, the computers on the network must all
have the same Subnet Mask and have a different IP Address. For
example, when using the above values on one computer you would want
to use an IP address of 102.55.92.2 on another computer and then specify
the same Subnet Mask.
Firewall
If your computer network utilizes a firewall, ensure that all ports required
are open. If possible, close the firewall software program or disconnect the
computer from the firewall to ensure it is not causing the problem.
Additional time
In some cases it may take a computer some additional time to detect
or see the network. If after booting the computer you are unable to see the
network, give the computer 2-3 minutes to detect the network. Windows users
may also want to try pressing the F5 (refresh) key when in Network
Neighborhood to refresh the network connections and possibly detect the
network
Additional troubleshooting
If after following or verifying the above recommendations you are still
unable to connect or see the network, attempt one or more of the below
recommendations.
If you have installed or are using TCP/IP as your protocol you can ping
another computer's IP address to verify if the computer is able to send and
receive data. To do this, Windows or MS-DOS users must be at a prompt and
Linux / Unix variant users must open or be at a shell.
Once at the prompt assuming, that the address of the computer you
wish to ping is 102.55.92.2, you would type:
ping 102.55.92.2
If you receive a response back from this address (and it is a different
computer), this demonstrates that the computer is communicating over the
network. If you are still unable to connect or see the network, it is possible
that other issues may be present.
Another method of determining network issues is to use the tracert
command if you are a MS-DOS or Windows user or the trace route command
http://www.computerhope.com/jargon/f/firewall.htm207
if you are a Linux / Unix variant user. To use this command you must be at
the command prompt or shell. Ortrace route 102.55.92.2
This should begin listing the hops between the computer and network
devices. When the connection fails, determine what device is causing the
issue by reviewingthe trace route listing.
Networking with DHCP
Task: Setting up a local area network with a Dynamic Host Control
Protocol (DHCP) server is easy. The DHCP server provides all the
information your computer needs to get up and running on the network. Once
connected, you will check network connectivity with the router and at least
one other peer on the network.
Procedures:
Getting connected
1. Before connecting your PC to the network, be sure the Windows XP
operating system is running on your computer. You will use Windows XP sp2
throughout this activity.
2. Next, open a terminal window on your computer by clicking on
Applications->Accessories->Terminal.
3. In the terminal window, type ipconfig and press Enter.
a. How many network devices are listed in the output? Record their names in
your worksheet.
b. Is there an IPv4 address listed for any of the network devices? If so, record
your
IP address (es) in your worksheet.
4. Connect your computer to a network switch using a patch cable. Did you
get a light on the switch? Record the port number you connected to in your
worksheet.