If table 4-2 does not lead you to the cause of the problem, go to
SYMPTOM TABLE TROUBLESHOOTING
Table 4-3 provides
of malfunction symptoms, indicators lit, probable cause for each symptom and
action for each probable cause. Select the symptom and indications that best define the problem in the printer. Next,
examine all the probable causes for that symptom. Select the cause that best matches the situation for which you are
troubleshooting. For each such cause there is a corrective action in the last column. Do the corrective action that matches
the probable cause you selected. When this task is completed, run a self-test to make sure the printer is again operating
REFERENCE TO A MAINTENANCE PROCEDURE
As you follow the direction in the troubleshooting table, you will be lead to a maintenance procedure which can correct the
fault. The reference will be to a paragraph in section III. Turn to that paragraph and do all the steps unless the reference
tells you to do only some of the steps. Then do only the steps called for in the reference.
ALTERNATIVE TROUBLESHOOTING PROCEDURES
When a failure causes a symptom which is not covered in the symptom index or not corrected by the troubleshooting
procedure, you must try alternative techniques.
a. Understand Principles of Operation. Sometimes the symptom with have no specific procedure given to
troubleshoot it. When this happens, remember that the equipment always operates the same way. By comparing the faulty
operation with expected or normal operation you may find the cause of the failure and be able to fix it.
b. Check the Circuits. All electronic equipment uses circuits to route power through the components. Any break
By running continuity checks on suspect circuits you may find the cause of the failure.
c. Check Past Maintenance Records. If the unusual failure occurred before, it should appear in the maintenance
records for the equipment. The records should also tell you have the failure was corrected. Use the same fix this time.
d. Trial and Error Repair. Usually trail and error repairs should be avoided. They are costly and can induce
additional symptoms. However, when your experience with the equipment leads you to suspect a definite cause, you
should try the repair as a last resort before shipping the equipment to depot for maintenance.