Determining Hardware and Configuration Problems
This article addresses the following objective in the "Domain 2.0: Diagnosing and Troubleshooting" section of the A+ Certification exam:
2.2: Identify basic troubleshooting procedures and good practices for eliciting problem symptoms from customers.
One of the most important aspects of troubleshooting anything is gathering information about the problem at hand and the symptoms it is showing. The computer technician should be able to effectively acquire information from the customer (user) concerning the nature of a problem, observe the symptoms of a malfunction to verify the problem, and then be able to practice basic troubleshooting methods to isolate and repair the problem.
Watching the Boot-Up Procedure
Carefully observing the steps of a boot-up procedure can reveal a great deal about the nature of problems in a system. Faulty areas can be included or excluded from possible causes of errors during the boot-up process.
Here are the observable actions of a working system's cold-boot procedure in their order of occurrence:
When power is applied, the power-supply fan activates.
The keyboard lights flash as the rest of the system components are being reset.
A Basic Input Output System (BIOS) message displays on the monitor.
A memory test flickers on the monitor.
The floppy disk drive access light comes on briefly.
The hard disk drive access light comes on briefly.
The system beeps, indicating that it has completed its Power-On Self-Tests and initialization process.
The floppy disk drive access light comes on briefly before switching to the hard drive. At this point, the BIOS is looking for additional instructions (boot information), first from the floppy drive and then from the hard drive (assuming the CMOS setup is configured for this sequence).
For Windows machines, the Starting Windows message appears onscreen.
Memorize the order of the series of observable events that occur during the normal (DOS) boot up.
If a section of the computer is defective, you will observe just some (or possibly none) of these events. By knowing the sections of the computer involved in each step, you can suspect a particular section of causing the problem if the system does not advance past that step. For instance, it is illogical to replace the floppy disk drive (step 5) when a memory test (step 4) has not been displayed on the monitor.
When a failure occurs, you can eliminate components as a possible cause by observing the number of steps the system completes in the preceding list. You can eliminate those subsystems associated with steps successfully completed. Focus your efforts only on those sections responsible for the symptom. When that symptom is cleared, the computer should progress to another step. However, another unrelated symptom might appear farther down the list. You should deal with this symptom in the same manner. Always focus on diagnosing the present symptom and eventually all the symptoms will disappear.