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
Paper jams
in inkjet printers are usually due to one of two things:
- A worn pickup roller
- The wrong type of paper
Print Quality
The major problem with this assembly can be described by “If you don’t use it, you lose it.
- An example of a quality problem is when you have thin, blank lines present in every line of text on the page
Faded print
will come out of the printer if there is no toner or low toner in the cartridge
- If it’s empty, replace it with a known, good, manufacturer- recommended toner cartridge.
- If it is not yet empty, shaking
it redistributes the toner and may provide better printing for some time
Paper-Feeding Problems
If your printer fails to pick up paper, it could indicate that the pickup rollers are too worn
- If your printer is consistently pulling multiple sheets of paper, you might want to try to increase the tension using this lever
Speckling on printed pages
This is where the pages have random dots of ink or other material on them as they print
- caused by stuff like paper dust or residue from envelopes, staples, or glue getting into the machinery
- Cleaning the printer and blowing it out with compressed air should clear up any speckling
Grinding noise
a printer symptom that could occur across all printer types.
- think about motors, gears, and rollers if you hear grinding
Incorrect page orientation
If a print job is not coming out correctly, such as the output is squeezed into a smaller area than a regular sheet of 8.5 × 11 paper, it may be that the paper size is improperly set
- To change the settings in Windows, open the Printers & Scanners app. Highlight the printer, choose Manage, and then select Printing Preferences
Intermittent Connectivity
is when the network sometimes connects, but it’s not consistently connected
Jitter
is variable in delay or the latency of data in a network
- Think of it as if someone had too much caffeine and they are shaking a bit
Latency
is a measure of time it takes for data to travel from one point to another in a network
- High latency looks like the connection is intermittent, simply because the delays are so long
Poor VoIP Quality
A bad or intermittent network connection
- If a network is suffering from poor VoIP quality, the administrator could give it a higher priority (QoS)
Port flapping
is when a switch port opens and closes very quickly
- The result is intermittent connectivity
CompTIA Troubleshooting Methodology
- Identify the problem
- Establish a theory of probable cause
- Test the theory to determine the cause
- Establish a plan of action to resolve the problem
- Verify full system functionality
- Document the findings, actions and outcomes
Lines down the printed pages
- dirty photosensitive drum
- scratched or damaged photosensitive drum
- worn-out or damaged fuser roller
- dirty feed roller
- scratched scanner glass
Garbled print
- incompatible firmware update
- corrupted or incompatible device driver
- communication error
Toner not fusing to paper
- faulty fuser unit
- incorrect paper type
- incorrect paper weight
- worn or damaged fuser roller
Paper Jams
- safety first
- worn pickup roller
- blocked sensor
Double/echo images on the print
- worn or damaged imaging drum
- dirty imaging drum
- defective drum cleaning mechanism
Multipage misfeed
- worn or damaged separation pad
Multiple Prints Pending in Queue
Step 1: check if print has paper, ink, toner
Step 2: check if printer is online
Step 3: restart the current print job
Step 4: delete and reprint
Step 5: stop/restart Print spooler service
Limited Connectivity
- error message “No internet access”
- do you have an APIPA address?
- can you communicate with remote devices
- faulty network cables and connections
Slow Network Speeds
- interface configurations (speed and duplex settings)
- damaged cable or poor connection
- network congestion
- malware
External Interference
primary concern is Electromagnetic Interference (EMI)
sources: fluorescent lights, power cables, generators, neighboring devices, microwave ovens, cordless phones, other Wi-Fi networks
Pinwheel of Death
is when the cursor in a Mac operating system is perpetually spinning, halting all other tasks that can be done
- cause by high resource consumption or malware
Loud noise, Loud clicking noise, Grinding noise
cause: damaged hard disk drive or fan
solution: replace hard disk drive or fan
System lockups, Sluggish Performance, or Application Crashes
cause: overheating or lack of RAM
solution: eliminate factors that contribute to overheating or upgrade RAM
Attempts to boot to incorrect device
cause: misconfigured BIOS
solution: adjust BIOS boot order
Continuous reboots
cause: bad RAM, faulty power supply, or CPU
solution/l replace RAM, power suppluy, or CPU
Fans spin - no power to other devices
cause: failing power supply or failing motherboard
solution: replace power supply or motherboard
CHKDSK
is a command line utility used to scan the HDD and attempt to repair files that have been damaged due to data corruption
Disk Defragmenter
is a utility organizes your files to make them more contiguous and accessible by the hard drive, therefore improving the speed of the drive
S.M.A.R.T or Read/write failure
cause: damaged hard drive
solution: Run CHKDSK if applicable and replace hard drive
Slow performance
cause: fragmented files are stored, or too many files stored
solution: run disk defragmenter, upgrade had drive, or delete unneeded files for more hard drive space
Failure to boot or bootable device not found
cause: misconfigured boot order, missing /corrupted OS, or bad hard drive
solution: adjust boot order, repair/reinstall OS, or replace hard drive
Drive not recognized
cause: flash drive may still be plugged in during boot, misconfigured boot order
solution: disconnect flash drive, or adjust boot order
Data loss/corruption
cause: damaged hard drive
solution: run CHKDSK if applicable, use data recovery software and replace hard drive
Missing drives in OS
cause: drive able not connected, drive not initialized or damaged drive
solution: reconnect drive cable, initialize drive in disk management or disk utility, or purchase new hard drive
Extended read/write times
cause: hard drive may be too full, slowing down system
solution: clear space on the hard drive
Video artifact or digital artifacts
are known as a distortion in video quality that could result in unwanted elements and discoloration on the screen’s image
cause: overheating GPU/Video card or defective GPU/ Video card
solution: cool down GPU/video card overall or replace GPU/Video card
High latency or jitter
cause: distance between access point and computer, interference
solution: reduce distance between device and access point, reduce surrounding devices that could cause interferences
Poor Voice over Internet quality
cause: VoIP QoS configurations is set to low priority
solution: configure VoIP QoS setting to high priority
Intermittent Wireless Connectivity
cause: wireless antenna is crimped or damaged, or far from access point
solution: replace wireless antenna or move device closer to access point
Limited connectivity
cause: router issues, DHCP issues, DNS misconfiguration, or share settings disabled
solution: resolve router issues, resolve DHCP issues, properly configure DHCP, or enable share settings
Application fails to close/crashes
cause: app needs an update, too many resources being used, overheating, malware infection
solution: update app, uninstall/repair/reinstall app, close application, close others apps, turn off phone, run antimalware
Applications fails to update
cause: malware infection
solution: update app, uninstall/repair/reinstall app, close applications, turn off phone, run antimalware
Streaks or lines down printed pages
cause: dirty print heads or dirty drum
solution: clean print heads or drum
Faded prints
cause: low toner or drum not storing proper charge
solution: replace toner or replace drum
Double/echo images on the print
cause: fault drum cleaning blade
solution: clean drum cleaning blade or replace
Toner smearing or not fused to paper
cause: fuser is not hot enough or replace fuser assembly
solution: increase fuser temperature of possible or replace fuser
Crease paper
cause: paper not placed in paper tray properly, dirty pickup rollers, faulty pickup rollers
solution: place stock of paper properly in tray, clean pickup rollers, or replace pickup rollers
Paper not feeding or multipage misfeed
cause: paper not placed in paper tray properly, dirty pickup rollers, faulty pickup rollers
solution: place stock of paper properly in tray, clean pick rollers, or replace pickup rollers
Paper jam
cause: paper not placed in paper tray properly, dirty pickup rollers, faulty pickup rollers
solutions: place stock of paper properly in tray, clean pickup rollers, or replace pickup rollers
No connectivity
cause: printer is not on, not pointed to correct DNS, or misconfigured printer settings
solution: turn on printer, correct DNS settings, or correct printer sharing settings
Garbled characters on paper
cause: wrong printer drivers installed
solution: install the correct printer drivers
Multiple prints pending in queue
cause: too many print jobs processed at the same time, or low amount of printer RAM (low memory errors)
solution: restart print queue or increase amount of RAM
Access denied
cause: don’t have sufficient privileges to print
solution: obtain permission to print
Color prints in wrong print color
cause: dirty printer cartridge nozzles or improper cartridge placement
solution: clean printer nozzles or adjust cartridge placement
Finishing issues (staples jams or hole punch)
cause: finisher sensor is dirty or obstructed
solution: clean sensor from obstruction, staples, adjust paper stock
Distorted geometry
can be adjusted in projectors by setting the keystone configuration to match the surface the image will be on
Input/output operations per second (IOPS)
represents the number of reads and writes that can be done in a second
- For example, a 15,000 rpm SATA drive with a 3 Gb/s interface is listed to deliver approximately 175–210 IOPS,
- whereas an SSD with a SATA 3 Gb/s interface is listed at approximately 8,600 IOPS (and that is one of the slower SSD drives)
Missing drives in OS
- The hard drive data cable or power cable may have become unseated.
- If you just added a drive, ensure that both drives have not been set to primary or
secondary and that the boot drive is set as primary on the first channel. - If the system uses SATA and you just added a drive, ensure that all the onboard SATA ports are enabled.
- If you just added a drive, ensure that there is no conflict between the new drive and another device.
- If you receive the “No boot device available, strike F1 to retry boot, F2 for setup utility” message, the cause could be incorrect drive geometry (probably not the case if this drive has been functioning properly before), bad CMOS battery, or inability to locate the active partition or master boot record
