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.
