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Diagnostic Worksheet

WHAT......................Vehicle & Engine Model
WHEN......................Date, Frequencies
WHERE......................Road Conditions
HOW......................Operating Conditions, Weather Conditions, Symptoms.

KEY POINTS
There are many operating conditions that lead to the malfunctions of engine components.
A good knowledge of such conditions can make trouble-shooting faster and more accurate.
In general, each customer may feel differently about a given problem. It is important to fully understand the symptoms or conditions for a customer complaint.
Utilize a diagnostic worksheet like the one shown in the worksheet sample in order to organize all the information for troubleshooting.
Some conditions may cause the malfunction indicator lamp to come on steady or blink and DTC to be detected.
Examples:
- Vehicle ran out of fuel, which caused the engine to misfire.
- Fuel filler cap was left off or incorrectly screwed on, allowing fuel to evaporate into the atmosphere [for models with EVAP (SMALL LEAK) diagnosis.




WORKSHEET SAMPLE