correct it. The proper troubleshooting routine may be
neglect the use of any test instruments such as
determined by using one of the three approaches shown
multimeters, voltmeters, ammeters, test lamps,
in figure 3-1 and described in the following test:
hydrometers, and pressure and vacuum gages which
a. Malfunction Approach.
The malfunction
may be available. To obtain the maximum number of
observed symptoms of trouble, question the vehicle
approach consists of referring to the troubleshooting
crew about the conditions under which the symptoms
table (table 3-4) and selecting the probable cause of a
occurred. The greater the number of symptoms of
particular malfunction. Table 3-4 lists various abnormal
troubles that can be evaluated, and the more detailed
operations and indications which may occur during
the knowledge of the conditions under which they
inspection and operation of the vehicle. It provides a list
occurred, the easier it will be to isolate the defect.
of probable causes of the malfunction, corrective
actions to be taken, and/or reference to the appropriate
troubleshooting routines for isolating the faulty circuit or
3-35. The troubleshooting information contained in
component.
this section parallels the concept of organizational
b. Test Approach. The test approach may be used
maintenance and the level of responsibility prescribed in
to isolate trouble to a particular system or circuit by
the Maintenance Allocation Chart (Appendix B).
performing the qualification procedure in table 3-3. The
qualification procedure is a progressive check-out
procedure, consisting of commands, responses and
electrical troubleshooting are presented in paragraph 3-
references to the appropriate troubleshooting routine to
be performed when abnormal results are obtained. The
qualification procedure can be used independently as a
3-37.
Troubleshooting Technique.
check-off list to certify correct operation or to requalify
systems after completion of corrective maintenance.
3-38. When a malfunction is detected perform a
troubleshooting routine to determine the probable cause
of the malfunction and the proper action to take to
3-5
