No Need to Ask for Help for Minor Computer Problems - Mouse, Floppy Drive, Printer, Hard Disk, Fan, Common Troubleshooting
Mouse
The analysis and repair of mouse faults are relatively simple. Most faults are caused by poor contact at the interface or buttons, broken wires, or dirt in the mechanical positioning system. A few faults are due to internal components or circuit cold soldering, mainly found in some inferior products, with LED and IC circuits damage being more common.
What to Do When Mouse Buttons Malfunction
1. If the mouse button shows no action, it may be because the button is too far from the microswitch on the circuit board or the switch needs time to rebound after use. Open the mouse and attach a plastic sheet of appropriate thickness under the mouse button. The thickness should be determined according to actual needs. After adjustment, the mouse can be used again.
2. If the mouse button cannot properly bounce back, it might be due to a cracked bowl-shaped contact in the microswitch below the button, especially as plastic springs tend to break over long-term use. For a three-button mouse, you can temporarily use one of the side buttons. For high-quality original brand mice, the microswitch can be desoldered, cleaned carefully, lubricated with grease, and then reassembled.
What to Do When You Can't Find Your Mouse
1. Poor contact between the mouse and the computer's serial port or PS/2 interface. Carefully reconnect the cables and restart the computer.
2. Damage to the motherboard's serial port or PS/2 interface, which is rare. In this case, you may need to replace the motherboard or use a multifunction card.
3. Poor contact in the mouse wiring, which is relatively common. This usually occurs at the data line and circuit board solder points inside the mouse. To fix it, open the mouse and resolder the data line connections using a soldering iron. If the issue lies within the mouse cable, it’s often due to aging, making replacement the quickest solution.
4. If the mouse is completely damaged, a new one will be needed.
5. If the mouse moves sluggishly, it could be due to accumulated dirt on the mechanical positioning rollers. Clean the rollers and other parts with alcohol, which should improve movement.
Floppy Drive
In daily computer usage, floppy drives are frequently used and thus prone to faults. However, most issues can be resolved with simple handling. Below are some common problems and solutions:
Issue One: Normal read/write operations but fails to recognize a second disk after switching.
Cause and Solution: The first disk functions normally, indicating that the step, seek, read, and write circuits are fine, but the drive fails to recognize a new disk after switching. Likely, the disk change mechanism is faulty. Ensure the optical coupler sends the correct signal for disk changes. Clean dust from the zero track detection sensor and check if the eject rod is correctly reset. Lubricate it with a little oil to ensure smooth operation.
Issue Two: Unstable operation, occasional normal read/write, mostly errors accompanied by noise.
Cause and Solution: Noise suggests a mechanical fault. Check the magnetic head loading structure. Adjust the screw that regulates the distance between the magnetic head and the disk to ensure proper alignment.
Printer
In daily life, printer malfunctions can delay important work if waited on repair personnel. Here are some self-repair methods without needing complex techniques or equipment:
Basic Repair Methods
When an issue arises, first use the printer's self-diagnosis system, indicated by lights or sounds. Then inspect the printer cables (including ports, channels) and analyze internal structures (such as paper trays, print heads). Test page printing or partial component tests can help identify the problem. Software issues can often be resolved by updating drivers or visiting official websites.
Practical Repair Techniques
1. Unclear Print Quality: This usually relates to hardware faults. Focus on key components like the print head. Perform automatic cleaning as per the manual. Wipe the area near the print head with soft, absorbent paper. If unresolved, reinstalling the driver may help.
2. Different Print Results from Preview: Usually due to improper settings. Adjust the file's "page properties" such as paper size, type, and number of characters per line.
3. No Response After Issuing Print Commands: Check if the power cord is properly connected; reinsert all cables while powered off and try another outlet. Enter BIOS settings to check parallel port settings. Use ECP mode if supported, otherwise try ECP+EPP or "Normal." If unresolved, focus on the printer cable, ensuring secure connections. Try swapping the cable or using substitution methods.
4. System Freeze During Large File Printing: Likely a software issue. Check disk space and delete unnecessary files or expand printer memory if possible.
5. Certain Fonts Not Printing: Delete problematic fonts and reinstall necessary ones via "My Computer → Control Panel → Fonts."
6. Partial or Incomplete Printing: Likely a software fault. Change printer port settings in Windows 95/98 by navigating to "Start → Settings → Control Panel → System → Device Manager → Ports → Printer Port → Driver → Change Driver → Show All Devices," changing "ECP Print Port" to "Printer Port."
Hard Disk
Fault Phenomenon One:
After turning on the computer, the screen displays: "Device error" or "Non-System disk or disk error, Replace and strike any key when ready."
Analysis and Handling: Generally, this is due to lost or incorrect hard disk parameters in CMOS. Re-enter the correct parameters in CMOS settings. If unsure, restore from backed-up CMOS information or use the "HDD AUTO DETECTION" option if available.
Fault Phenomenon Two:
After turning on the computer, the "WAIT" prompt lingers for a long time before showing "HDD Controller Failure."
Analysis and Handling: Likely due to poor contact or incorrect connection of the hard disk cable. Check connections and ensure the red stripe on the data cable aligns with the power cable.
Fault Phenomenon Three:
After turning on the computer, the screen displays: "Invalid partition table," and the hard disk cannot boot, though C drive is recognized when booted from a floppy.
Analysis and Handling: Likely due to errors in the partition table. Use NDD to repair, which checks and fixes partition table errors. If infected by a virus, use antivirus software before repairing with NDD.
Fault Phenomenon Four:
After turning on the computer and completing self-check, booting from the hard disk causes a system freeze or displays: "No ROM Basic, System Halted."
Analysis and Handling: Likely due to corrupted or virus-infected boot programs, missing boot flags in the partition table, or altered end flag 55AAH. Boot from a floppy and execute the command "FDISK/MBR."
Fault Phenomenon Five:
After turning on the computer, the screen displays: "Error loading operating system" or "Missing operating system."
Analysis and Handling: Likely due to errors in the DOS boot record. Use NDD to repair or rewrite the DOS boot record using the "sys c:" command.
Fan
With increasing numbers of circuits integrated into microprocessors and rising energy consumption, heat dissipation becomes crucial. Various cooling systems exist, including water cooling, semiconductor cooling, and oil cooling. However, the most commonly used and affordable method is air cooling through fans. In desktop computers, two main devices use cooling fans: the power supply and the CPU. While power supply fans generally last longer due to design, CPU fans are consumables. Below are some common issues and their solutions:
Common Fault One: A 486 CPU cooling fan suddenly emits unusually loud noise during recent use, louder than the power supply. Upon inspection, years of neglect have led to excessive dust accumulation and dried-out motor lubricant causing a motor-like humming sound.
Solution: Separate the fan and heatsink, clean both with water or soft paper, and use sewing machine oil or toy car grease to lubricate the motor core.
Common Fault Two: A Socket 370 cooling fan recently shifted from its fixed position. Investigation revealed that the fastening clips had failed, leading to resonance-induced displacement.
Solution: Replace with new fastening clips.
Common Fault Three: A newly assembled Duron 800 PC stopped working after running continuously unattended for hours. Upon inspection, the motherboard BIOS' automatic energy-saving function was enabled, causing the system to suspend and stop the CPU fan, resulting in overheating and burning out the CPU.
Solution: Review BIOS settings and disable Suspend mode.
Common Fault Four: While the fan rotates, there is intermittent "tapping" collision sounds. Inspection revealed tangled data and power lines occasionally hitting the fan blades.
Solution: Securely tie up loose data and power lines with rubber bands or tape to avoid interference.
Common Fault Five: A new CPU cooling fan produced excessive noise and moved sluggishly after less than a week of use. Initially slow with significant noise upon startup, it eventually normalized. Thought to be a motor issue, replacing with a similar fan did not resolve the issue. Analysis showed low indoor temperatures affecting bearing lubricant efficiency.
Solution: Add anti-freeze lubricant and ensure appropriate environmental temperature.