When diagnosing a specific problem, organized troubleshooting is a must.
The complexity of a modern automobile demands that you approach any problem
in a logical, organized manner. There are certain troubleshooting techniques
that are standard:
- Establish when the problem occurs. Does the problem appear only under
certain conditions? Were there any noises, odors, or other unusual symptoms?
- Isolate the problem area. To do this, make some simple tests and observations;
then eliminate the systems that are working properly. Check for obvious
problems such as broken wires, dirty connections or split/disconnected vacuum
hoses. Always check the obvious before assuming something complicated is
the cause.
- Test for problems systematically to determine the cause once the problem
area is isolated. Are all the components functioning properly? Is there
power going to electrical switches and motors? Is there vacuum at vacuum
switches and/or actuators? Is there a mechanical problem such as bent linkage
or loose mounting screws? Performing careful, systematic checks will often
turn up most causes on the first inspection without wasting time checking
components that have little or no relationship to the problem.
- Test all repairs after the work is done to make sure that the problem
is fixed. Some causes can be traced to more than one component, so a careful
verification of repair work is important in order to pick up additional
malfunctions that may cause a problem to reappear or a different problem
to arise. A blown fuse, for example, is a simple problem that may require
more than another fuse to repair. If you don't look for a problem that caused
a fuse to blow, a shorted wire (for example) may go undetected.
Experience has shown that most problems tend to be the result of a fairly
simple and obvious cause, such as loose or corroded connectors or air
leaks in the intake system. This makes careful inspection of components
during testing essential to quick and accurate troubleshooting.
