Comptus A70-DL0, Инструкция по эксплуатации

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15
Trouble Shooting Philosophy
Effective trouble shooting requires that problem
locations be systematically eliminated until the
problem is found.
There are four basic questions to answer when
trouble shooting (Ref. #1):
1. Did it ever work right?
2. What are the symptoms that tell you it’s not
working right?
3. When did it start working badly or stop
working?
4. What other symptoms showed up just before,
just after, or at the same time as the failure?
It is best to write down any clues you may
obtain. Be sure to write down anything unusual.
The response to question #3 should probably not
be 3:04 P.M.. A useful response might be, “Just
after an electrical storm.” or, “Just after it fell off
the shelf.”
Double check all the simple solutions to the
problem before searching for complex ones. If
the problem occurs right after installation, it
probably has a simple solution.
If an automobile engine cranks, but doesn’t start,
make sure there is fuel in the tank before replac-
ing the engine. If the electronic equipment
doesn’t function verify that it has power and is
turned on.
Systems containing parts which can be quickly
interchanged are easy to trouble shoot. Swap
parts until the problem moves. The location has
then been narrowed to the part that caused the
problem to move.
Sometimes there are multiple problems. These
reveal themselves in layers much like peeling an
onion.
It often helps to explain the problem to another
person, even if that person is not knowledgeable
about the particular piece of equipment.
This does two things. First it requires you to
organize the situation so it can be explained to
another. Secondly, it may turn out that you are
so familiar with the situation that you have
overlooked the obvious. Another person unfa-
miliar with the equipment may be able to help.
If you are unable to solve the problem, put it
aside until the next day. Some new thoughts will
probably occur while working on another
project.
References
1. “Troubleshooting is More Effective with the
Right Philosophy”, Robert A. Pease, Electronic
Design News, January 5, 1989.