5. Hardware and Networking Troubleshooting (29%) Flashcards
- Identify the Problem
- Gather information from the user, identify user changes, and, if applicable, perform backups before making changes
- Inquire regarding environmental or infrastructure changes
- Establish a theory of probable cause (question the obvious)
- If necessary, conduct external or internal research based on symptoms
- Test the theory to determine the cause
- Once the theory is confirmed,
determine the next steps to resolve the problem - If the theory is not confirmed, re-establish a new theory or escalate
- Establish a plan of action to resolve the problem and implement the solution
- Refer to the vendor’s
instructions for guidance
- Verify full system functionality
and, if applicable, implement
preventive measures
After fixing the system, or all the systems affected by the problem, go back and verify full functionality.
- Document the findings, actions, and outcomes
- Always document your work
so that you or someone else can learn from the experience. - Good documentation of past troubleshooting can save hours of stress in the future.
Power-on self-test (POST) beeps
can be caused by many things since they are subjected to the manufacturer of the motherboard
- If there’s more than one beep, the number, duration, and pattern of the beeps can sometimes tell you what component is causing the problem
- If the POST card stops at a certain number, you can look up that number in the manual for the card to determine the problem
Proprietary crash screens (blue screen of death [BSOD]/
pinwheel)
is a Windows bases error screen that is usually fixed by recording and researching the error code or STOP code displayed
- caused by the physical memory failing
- Sometimes switching the slot that the RAM is in will help, but more often than not the RAM needs to be replaced
Black screen on bootup
a computer with no video output
cause: problem with external video card
solution: update video driver or replace video card
No power
cause: failed power supply or power plug issues
solution: replace power supply or verify power plug
when you try to power it up, make sure the outlet is functional and try a new power cable
Sluggish performance
While applications, normal usage, and so on can contribute to this, another offender could be malware or a virus
- Check RAM and CPU usage and if an application is out of control, it could be infected with malware
Overheating
Dust, dirt, grime, smoke, and other airborne particles can become caked on the inside of computers and cause this
Burning smell
cause: malfunction PSU
solution: Disconnect PSU and replace
Intermittent shutdown
are hard to troubleshoot but are most likely hardware related
cause: overheating (dust build up, environmental factors)
solution: reduce dust or place device in a cooler environment
Application crashes
most likely one of two things: a poorly coded app or faulty memory
- produce error messages such as general protection faults (GPFs)
Capacitor swelling
they will swell and brownish- red electrolyte residue may seep out of the vents in the top
- best option is to replace the motherboard
- second option is to drain the energy from the failed capacitor and replace it
Light-emitting diode (LED) status indicators
status indicator lights that can help you identify operational features or problems with a device
- the power light doesn’t come on and the device has no power, always obey the first rule of troubleshooting: check your connections first!
Bootable device not found
Failure to boot at all likely means the drive is not properly connected or it’s dead
Data loss/corruption
A failing hard drive might exhibit data loss or corruption or very slow (extended) read/write times
- If the drive doesn’t have enough free space (at least 10 percent), it can slow down dramatically.
- The solution here is to remove files or old applications to free up space and look at defragmenting the hard drive. If problems persist, consider formatting the hard drive and reinstalling the OS
Self-Monitoring, Analysis, and Reporting Technology (S.M.A.R.T.)
is used for hard drive diagnostics. This feature will provide you with a status update of your system
- In practice, though, it seems to help manufacturers locate persistent issues by identifying hard drive design flaws more than it helps end users avoid catastrophic data losses
Missing Drives in OS
Sometimes you have a storage device installed, but you are unable to find it in Windows File Explorer or the Finder in macOS
- This could be a connection issue, or perhaps the drive hasn’t been properly set up for use
Incorrect data source
means that the device won’t display anything
- may be a button on the monitor or projector to bring up an onscreen menu and configure the correct source, or you may need to use the device’s remote control
Physical cabling issues
disconnecting and reconnecting the video cables or another cable in the event of incorrect data source
Burned-out bulb
Projector bulbs have a limited shelf life, and the heat produced by a projector and its bulb can shorten it even further
- The only resolution is to replace the bulb
Fuzzy Image
It could be caused by external interference such as fluorescent lights, magnetic devices, and electrical devices such as fans, lamps, and speakers.
- it could be that the resolution is set for something that the display can’t handle, or at least can’t handle well
Display Burn-In
is when a screen has the remnants of an image that was on the screen prior
- cause: very high brightness for extended amount of time; screen is overheating
- solution: turn off screen, set screensaver to an image that is always moving, replace screen
Dead Pixels
are spots on the screen that never “fire,” or light up
- The only solution for this is to replace the monitor
Flashing Screen
Sometimes a display will either subtly flicker or flash off and on.
- Those two symptoms are caused by different things.
- Flickering screens are most commonly caused by the backlight starting to fail.
- In those cases, replace the backlight
Incorrect Color Display
This can happen when the LCD monitor’s controller board starts to fail and doesn’t perform color mapping correctly
- If switching the monitor makes the problems go away, it’s probably time to replace the monitor
Dim Image
If this is a problem with the monitor itself, it’s most likely caused by a failing backlight
- If no amount of adjustment makes the image bright enough for normal use, then replace the backlight
Audio Issues
The most common reason people have audio problems is because something is muted, but it could also be a cable or connection issue
Intermittent Projector Shutdown
projectors create a lot of heat
- Most projectors have an air filter to keep dust and debris out of it— check to ensure that’s clean and replace it if necessary
Poor battery health
As batteries get older, they are not able to hold as much of a charge and, in some cases, are not able to hold a charge at all
- it’s likely that the battery needs to be replaced
Swollen Battery
It can be caused by a number of things, including manufacturer defects, age, misuse, using the wrong adapter for charging, or leaving the laptop constantly plugged into a wall outlet
- If you have this, turn the device off immediately and make sure that it’s not plugged into a charger
Improper charging
If the device doesn’t appear to charge, the same culprits apply: it could be the outlet, the adapter, or the device itself
Broken screen
If a screen does get broken, either replace the screen or replace the device.
Liquid damage
If a laptop gets doused in a liquid, it’s best to turn it off as soon as possible and let it dry out
- Disassemble the components, clean them with water and the cloth, and let them thoroughly dry. Reassemble, and see if it works
Overheating
It could be from overuse, or perhaps it did not have proper ventilation (for example, if it was stuffed into someone’s pocket or purse)
- The first is to test or replace the battery, as that’s the most likely culprit. If overheating still happens, you may have to replace the device
Physically damaged ports
Sometimes the ports are obviously damaged, and other times they simply fail to work
- the only remedy is to replace the port, which usually means replacing several components, including the motherboard on a laptop, or replacing the entire mobile device
Malware
is malicious software designed to damage, disrupt, or gain unauthorized access to a computer system
- one of the most common security risks that you will encounter