Important Preliminary Checks Before Starting 
Perform the 
Diagnostic System Check - Engine Controls
 before using the symptom tables. Verify that all of the following conditions are true:
|     •  | The engine control module (ECM) and the malfunction indicator lamp (MIL) are operating correctly. | 
 
|     •  | There are no diagnostic trouble codes (DTCs) stored. | 
 
|     •  | The scan tool data is within the normal operating range. | 
 
|     •  | Verify the customer concern and locate the correct symptom listed below. Inspect items indicated under that symptom. | 
 
|     •  | Several of the symptom procedures direct the technician to perform a visual/physical inspection. This important step can lead the technician to the cause of the problem without further checks and can save valuable time. | 
 
|     •  | Verify the correct installation and operation of electronic options, such as lights and cellular phones. | 
 
- Use the following tables when diagnosing a symptom concern:
 
-  If the condition cannot be isolated using the appropriate table, refer to 
Intermittent Conditions
 for further diagnosis.