Intermittent Diagnostic Techniques: Notes

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Intermittent diagnostic techniques help find and isolate the root cause of intermittent faults associated with the PCM. The material is organized to help find the fault and perform the repair. There are examples that illustrate the diagnostic techniques. The process of finding and isolating an intermittent, starts with recreating a fault symptom, accumulating PCM data and comparing that data to typical values and analyzing the results.

Before proceeding, be sure that:

Customary mechanical system tests and inspections do not reveal a problem. (Remember, mechanical component problems can make a PCM system react abnormally.)
Review Technical Service Bulletins (TSBs) and OASIS messages, if available.
Quick Test and associated Pinpoint diagnosis have been completed without finding a fault, and the symptom is still occurring.