Diagnostic Process
Diagnostic steps are taken to identify the root cause of the problem, and it is necessary that all technicians must understand to troubleshoot and diagnose the engines. The most effective type of diagnostic process is a funnel diagnostic process. Funnel diagnostic process is a step by the procedure to identify the problem. The first step in diagnosis is to verify that the concern or problem exists. The second step is to perform a visual inspection of the problem area to check for some obvious issues like fuel leakage, pipe disconnects, corrosion, oil levels and any required repairs. All relevant tests must be performed like a paper test, smoke test, battery voltage, spark test and ensure adequate fuel levels and fuel pump pressure.
(Halderman)
Each finding must be recorded in a diagnosis worksheet for all the identified issues and inspection details and matched against the diagnostic trouble codes as defined in the rule book. After that, the technician must cross check the diagnostic codes in technical service bulletins for repair procedures of the identified issues. The scanned results must be carefully inspected based on the acquired data from all diagnostic procedures performed.
Finally, the problem must be narrowed down to a specific location of the engine which can be either a cylinder or any other part that is identified to be the root cause of the problem. Afterwards, repair the identified problem and ensure that the fixed issue was the only root cause of the issue reported. At the end of the diagnostic procedure, the fixes and repairs must be tested verified thoroughly by all possible means including a test drive of the vehicle. Along with a verification of the repair, it is also important to verify that no additional problem has been introduced during the repair. A successful diagnosis is the one that follows all steps, conducts a thorough visual inspection and checks for any malfunctions. In the end, ensure to clean the vehicle.
(Halderman)
Works Cited
Halderman, James D. Advanced Engine Performance Diagnosis. 5th ed. Upper Saddle River,
N.J.: Pearson/Prentice Hall, 2011. Print.
