View Full Version : Troubleshooting

February 12th, 2010, 05:33 PM
Before diving into the specifics, a few essential checks which will often diagnose or even fix the problem.
Visual inspection
This one doesn't even require any specific equipment, other than maybe a magnifying glass. Give the item a thorough visual examination and note anything out of the ordinary. Things to look for include:
Scorched or burnt-out components
Residue from leaking components
Broken wires, connectors or PCB tracks

It helps to clean dirty equipment up before inspection, although excessive scrubbing can of course itself lead to yet more problems!
Reseat cards, cables and ICs
Sometimes, simply reseating components is enough to revive even a completely dead machine. It's easiest to start with larger components (expansion cards, cable connectors) first and, if this doesn't help, work down to smaller parts (ICs, crystals, etc.).
Power supply
A faulty power supply can cause all manner of strange and often otherwise inexplicable symptoms. Use a voltmeter to ensure all power rails are within the manufacturers tolerances (or if the tolerances are unknown, that the voltages are at least sane). If an oscilloscope is available, this can be used to check for ripple on DC power rails.
Common, model-specific problems
Similar machines often fail in similar ways. Use your favourite search engine to look for common problems with your specific hardware (and hopefully their solutions).
General Problems
Dead computer (blank screen, no response)

Garbage screen (random characters/colours)
Distorted image
Snow (TV screen)

Sticking keys
Intermittent keys
Nonfunctional keys

Disk Drive
Cleaning heads